Create a connection to Couchbase by navigating to the Connections page in the Sync App application and selecting the corresponding icon in the Add Connections panel. If the Couchbase icon is not available, click the Add More icon to download and install the Couchbase connector from the CData site.

Required properties are listed under the Settings tab. The Advanced tab lists connection properties that are not typically required.

Connecting to Couchbase

To connect to data, set the Server property to the hostname or IP address of the Couchbase server(s) you are authenticating to.

If your Couchbase server is configured to use SSL, you can enable it either by using an https URL for Server (like https://couchbase.server), or by setting the UseSSL property to True.

Couchbase Analytics

By default, the Sync App connects to the N1QL Query service. In order to connect to the Couchbase Analytics service, you will also need to set the CouchbaseService property to Analytics.

Couchbase Cloud

Set the following to connect to Couchbase Cloud:

• AuthScheme: Set this to Basic.
• ConnectionMode: Set this to Cloud.
• DNSServer: Set this to a DNS server. In most cases, this should be a public DNS service like 1.1.1.1 or 8.8.8.8.
• SSLServerCert: Set this to the TLS/SSL certificate to be accepted from the server. Any other certificate that is not trusted by the machine is rejected. Alternatively, set "*" to accept all certificates.

Authenticating to Couchbase

The Sync App supports several forms of authentication. Couchbase Cloud only accepts Standard authentication, while Couchbase Server accepts Standard authentication, client certificates, and credentials files.

Standard Authentication

To authenticate with standard authentication, set the following:

• AuthScheme: Set this to Basic.
• User: The user authenticating to Couchbase.
• Password: The password of the user authenticating to Couchbase.

Client Certificates

The Sync App supports authenticating with client certificates when SSL is enabled. To use client certificate authentication, set the following properties:

• AuthScheme: Set this to SSLCertificate.
• SSLClientCertType: The type of client certificate set within SSLClientCert.
• SSLClientCert: The client certificate in the format given by SSLClientCertType.
• SSLClientCertPassword (optional): The password of the client certificate, if it is encrypted.
• SSLClientCertSubject (optional): The subject of the client certificate, which, by default, is the first certificate found in the store. This is required if more than one certificate is available in the certificate store.

Credentials File

You can also authenticate using using a credentials file containing multiple logins. This is included for legacy use and is not recommended when connecting to a Couchbase Server that supports role-based authentication.

• AuthScheme: Set this to CredentialsFile.
• CredentialsFile: The path to the credentials file. Refer to Couchbase's documentation for more information on the format of this file.

Couchbase is a schema-free document database that provides high performance, availability, and scalability. These features are not necessarily incompatible with a standards-compliant query language like SQL-92.

The Sync App models the schema-free Couchbase objects into relational tables and translates SQL queries into N1QL or SQL++ (Analytics) queries to get the requested data. In this section we will show various schemes that the Sync App offers to bridge the gap with relational SQL and a document database.

Automatic Schema Discovery

When the Sync App first connects to Couchbase, it opens each bucket and scans a configurable number of rows from that bucket. It uses those rows to determine the columns in that bucket and their data types, as well as how to build flavored and child tables for any arrays within those documents. For Couchbase Enterprise version 4.5.1 and later, the Sync App may can also be configured to use the INFER command when TypeDetectionScheme is set to INFER. This allows the Sync App to get a more accurate column listing for the bucket, and to detect more complex flavors.

When using the Analytics service, the Sync App only does column and child table detection. Flavored tables are provided by Couchbase itself using shadow datasets. Also, Analytics mode does not currently have INFER support, so only row scan is supported.

For more details, refer to Automatic Schema Discovery to see how flavored tables and child tables are modelled from Couchbase data. Setting NumericStrings is also recommended as it can avoid type detection issues with certain kinds of text data.

Custom Schema Definitions

Optionally, you can use Custom Schema Definitions to project your chosen relational structure on top of a Couchbase object. This allows you to define your chosen column names, their data types, and the locations of their values in the Couchbase document.

Query Mapping

See Query Mapping for more details on how various N1QL and SQL++ operations are represented as SQL.

Vertical Flattening

See Vertical Flattening for more details on how arrays and objects are mapped into fields.

JSON Functions

See JSON Functions for more details on how to extract data from raw JSON strings.

Child Tables

If the documents within a bucket contain fields with arrays, then the Sync App will expose those fields as their own tables in addition to exposing them as JSON aggregates on the main table. The structure of these child tables depends upon whether the array contains objects or primitive values.

Array Child Tables

If the arrays contain primitive values like numbers or strings, the child table will have only two columns: one called "Document.Id" which is the primary key of the document containing the array, and one called "value" which contains the value within the array. For example, if the bucket "Games" contains these documents:

/* Primary key "1" */
{
  "scores": [1,2,3]
}

/* Primary key "2" */
{
  "scores": [4,5,6]
}

The Sync App will build a table called "Games_scores" containing these rows:

Document.Id	value
1	1
1	2
1	3
2	4
2	5
2	6

Object Child Tables

If the arrays contain objects, the child table will have a column for each field that occurs within the objects, as well as a "Document.Id" column which contains the primary key of the document containing the array. For example, if the bucket "Games" contains these documents:

/* Primary key "1" */
{
  "moves": [
    {"piece": "pawn", "square": "c3"},
    {"piece": "rook", "square": "d5"}
  ]
}

/* Primary key "2" */
{
  "moves": [
    {"piece": "knight", "square": "f1"},
    {"piece": "bishop", "square": "e4"}
  ]
}

The Sync App will build a table called "Games_moves" containing these rows:

Document.Id	piece	square
1	pawn	c3
1	rook	d5
2	knight	f1
2	biship	e4

NewChildJoinsMode

Note that the above data model is not fully relational, which has important limitations for use-cases that involve complex JOINs or DML operations on child tables. The NewChildJoinsMode connection property exposes an alternative data model which avoids these limitations. Please refer to its page in the connection property section of the documentation for more details.

Flavored Tables

The Sync App can also detect when there are multiple types of documents within the same bucket, as long as TypeDetectionScheme is set to Infer or DocType and CouchbaseService is set to N1QL. These different types of documents are exposed as their own tables containing only the appropriate rows.

For example, the bucket "Games" contains documents which have a "type" value of either "chess" or "football":

/* Primary key "1" */
{
  "type": "chess",
  "result": "stalemate"
}

/* Primary key "2" */
{
  "type": "chess",
  "result": "black win"
}

/* Primary key "3" */
{
  "type": "football",
  "score": 23
}

/* Primary key "4" */
{
  "type": "football",
  "score": 18
}

The Sync App will create three tables for this bucket: one called "Games" which contains all the documents:

Document.Id	result	score	type
1	stalemate	NULL	chess
2	black win	NULL	chess
3	NULL	23	football
4	NULL	18	football

One called "Games.chess" which contains only documents where the type is "chess":

Document.Id	result	type
1	stalemate	chess
2	black win	chess

And one called "Games.football" which contains only documents where the type is "football":

Document.Id	score	type
3	23	football
4	18	football

Note that the Sync App will not include columns in a flavored table that are not defined on the documents in that flavor. For example, even though both the "result" and "score" columns are included on the base table, "Games.chess" only includes "result" and "Games.football" only includes "score".

Flavored Child Tables

It is also possible for a flavored table to contain arrays, which will become their own child tables. For example, if the bucket "Games" contains these documents:

/* Primary key "1" */
{
  "type": "chess",
  "results": ["stalemate", "white win"]
}

/* Primary key "2" */
{
  "type": "chess",
  "results": ["black win", "stalemate"]
}

/* Primary key "3" */
{
  "type": "football",
  "scores": [23, 12]
}

/* Primary key "4" */
{
  "type": "football",
  "scores": [18, 36]
}

Then the Sync App will generate these tables:

Table Name	Child Field	Flavor Condition
Games
Games_results	results
Games_scores	scores
Games.chess		"type" = "chess"
Games.chess_results	results	"type" = "chess"
Games.football		"type" = "football"
Games.football_scores	scores	"type" = "football"

The Sync App maps SQL-92-compliant queries into corresponding N1QL or SQL++ queries. Although the mapping below is not complete, it should help you get a sense for the common patterns the Sync App uses during this transformation.

SELECT Queries

The SELECT statements are translated to the appropriate N1QL SELECT query as shown below. Due to the similarities between SQL-92 and N1QL, many queries will simply be direct translations.

One major difference is that when the schema for a given Couchbase bucket exists in the Sync App, a SELECT * query will be translated to directly select the individual fields in the bucket. The Sync App will also automatically create a Document.Id column based on the primary key of each document in the bucket.

SQL Query	N1QL Query
SELECT * FROM users	SELECT META(`users`).id AS `id`, ... FROM `users`
SELECT [Document.Id], status FROM users	SELECT META(`users`).id AS `Document.Id`, `users`.`status` FROM `users`
SELECT * FROM users WHERE status = 'A' OR age = 50	SELECT META(`users`).id AS `id`, ... FROM `users` WHERE TOSTRING(`users`.`status`) = "A" OR TONUMBER(`users`.`age`) = 50
SELECT * FROM users WHERE name LIKE 'A%'	SELECT META(`users`).id AS `id`, ... FROM `users` WHERE TOSTRING(`users`.`name`) LIKE "A%"
SELECT * FROM users WHERE status = 'A' ORDER BY [Document.Id] DESC	SELECT META(`users`).id AS `id`, ... FROM `users` WHERE TOSTRING(`users`.`status`) = "A" ORDER BY META(`users`).id DESC
SELECT * FROM users WHERE status IN ('A', 'B')	SELECT META(`users`).id, ... FROM `users` WHERE TOSTRING(`users`.`status`) IN ["A", "B"]

Note that conditions can include extra type functions if the Sync App detects that a type conversion may be necessary. You can disable these type conversions using the StrictComparison property. For clarity, the rest of the N1QL samples are shown without these extra conversion functions.

USE KEYS Optimizations

When a query has either equals or IN clause that targets the Document.Id column, and there is no OR clause to override it, the Sync App will convert the Document.Id filter into a USE KEYS clause. This avoids the overhead of scanning an index because the document keys are already known to the N1QL engine (this optimization does not apply to the Analytics CouchbaseService).

SQL Query	N1QL Query
SELECT * FROM users WHERE [Document.Id] = '1'	SELECT ... FROM `users` USE KEYS ["1"]
SELECT * FROM users WHERE [Document.Id] IN ('2', '3')	SELECT ... FROM `users` USE KEYS ["2", "3"]
SELECT * FROM users WHERE [Document.Id] = '4' OR [Document.Id] = '5'	SELECT ... FROM `users` USE KEYS ["4", "5"]
SELECT * FROM users WHERE [Document.Id] = '6' AND status = 'A'	SELECT ... FROM `users` USE KEYS ["6"] WHERE `status` = "A"

In addition to being used for SELECT queries, the same optimization is performed for DML operations as shown below.

Child Tables

As long as all the child tables in a query share the same parent, and they are combined using INNER JOINs on their Document.Id columns, the Sync App will combine the JOINs into a single UNNEST expression. Unlike N1QL UNNEST queries, you must explicitly JOIN with the base table if you want to access its fields.

SQL Query	N1QL Query
SELECT * FROM users_posts	SELECT META(`users`).id, `users_posts`.`text`, ... FROM `users` UNNEST `users`.`posts` AS `users_posts`
SELECT * FROM users INNER JOIN users_posts ON users.[Document.Id] = users_posts.[Document.Id]	SELECT META(`users`).id, `users`.`name`, ..., `users_posts`.`text`, ... FROM `users` UNNEST `users`.`posts` AS `users_posts`
SELECT * FROM users INNER JOIN users_posts ... INNER JOIN users_comments ON ...	SELECT ... FROM `users` UNNEST `users`.`posts` AS `users_posts` UNNEST `users`.`comments` AS `users_comments`

Flavor Tables

Flavored tables always have the appropriate condition included when you query, so that only documents from the flavor will be returned:

SQL Query	N1QL Query
SELECT * FROM [users.subscriber]	SELECT ... FROM `users` WHERE `docType` = "subscriber"
SELECT * FROM [users.subscriber] WHERE age > 50	SELECT ... FROM `users` WHERE `docType` = "subscriber" AND `age` > 50

Aggregate Queries

N1QL has several built-in aggregate functions. The Sync App makes extensive use of this for various aggregate queries. See some examples below:

SQL Query	N1QL Query
SELECT Count(*) As Count FROM Orders	SELECT Count(*) AS `count` FROM `Orders`
SELECT Sum(price) As total FROM Orders	SELECT Sum(`price`) As `total` FROM `Orders`
SELECT cust_id, Sum(price) As total FROM Orders GROUP BY cust_id ORDER BY total	SELECT `cust_id`, Sum(`price`) As `total` FROM `Orders` GROUP BY `cust_id` ORDER BY `total`
SELECT cust_id, ord_date, Sum(price) As total FROM Orders GROUP BY cust_id, ord_date Having total > 250	SELECT `cust_id`, `ord_date`, Sum(`price`) As `total` FROM `Orders` GROUP BY `cust_id`, `ord_date` Having `total` > 250

Insert Statements

The SQL INSERT statement is mapped to the N1QL INSERT statement as shown below. This works the same for both top-level fields as well as fields produced by Vertical Flattening:

SQL Query	N1QL Query
INSERT INTO users([Document.Id], age, status) VALUES ('bcd001', 45, 'A')	INSERT INTO `users`(KEY, VALUE) VALUES ('bcd001', { "age" : 45, "status" : "A" })
INSERT INTO users([Document.Id], [metrics.posts]) VALUES ('bcd002', 0)	INSERT INTO `users`(KEY, VALUE) VALUES ('bcd002', {"metrics': {"posts": 0}})

Child Table Inserts

Inserts on child tables are converted internally into N1QL UPDATEs using array operations. Since that this does not create the top-level document, the Document.Id provided must refer to a document that already exists.

Another limitation of child table inserts is that multi-valued inserts must all use the same Document.Id. The provider will verify this before modifying any data and raise an error if this constraint is violated.

SQL Query	N1QL Query
INSERT INTO users_ratings([Document.Id], value) VALUES ('bcd001', 4.8), ('bcd001', 3.2)	UPDATE `users` USE KEYS "bcd001" SET `ratings` = ARRAY_PUT(`ratings`, 4.8, 3.2)
INSERT INTO users_reviews([Document.Id], score) VALUES ('bcd002', 'Great'), ('bcd002', 'Lacking')	UPDATE `users` USE KEYS "bcd001" SET `ratings` = ARRAY_PUT(`ratings`, {"score": "Great"}, {"score": "Lacking"})

Bulk Insert Statements

Bulk inserts are also supported the SQL Bulk Insert is converted as shown below:

INSERT INTO users#Temp([Document.Id], KEY, VALUE) VALUES('bcd001', 45, "A")
INSERT INTO users#Temp([Document.Id], KEY, VALUE) VALUES('bcd002', 24, "B")
INSERT INTO users SELECT * FROM users#Temp

is converted to:

INSERT INTO `users` (KEY, VALUE) VALUES
  ('bcd001', {"age": 45, "status": "A"}),
  ('bcd002', {"age": 24, "status": "B"})

Like multi-valued inserts on child tables, all the rows in a bulk insert must also have the same Document.Id.

Update Statements

The SQL UPDATE statement is mapped to the N1SQL UPDATE statement as shown below:

SQL Query	N1QL Query
UPDATE users SET status = 'C' WHERE [Document.Id] = 'bcd001'	UPDATE `users` USE KEYS ["bcd001"] SET `status` = "C"
UPDATE users SET status = 'C' WHERE age > 45	UPDATE `users` SET `status` = "C" WHERE `age` > 45

Child Table Updates

When updating a child table, the SQL query is converted to an UPDATE query using either a "FOR" expression or an "ARRAY" expression:

SQL Query	N1QL Query
UPDATE users_ratings SET value = 5.0 WHERE value > 5.0	UPDATE `users` SET `ratings` = ARRAY CASE WHEN `value` > 5.0 THEN 5 ELSE `value` END FOR `value` IN `ratings` END
UPDATE users_reviews SET score = 'Unknown' WHERE score = ''	UPDATE `users` SET `$child`.`score` = 'Unknown' FOR `$child` IN `reviews` WHEN `$child`.`score` = "" END

Flavor Table Updates

Like flavor table SELECTs, UPDATEs on flavor tables always include the appropriate condition, so only docments belonging to the flavor are affected:

SQL Query	N1QL Query
UPDATE [users.subscriber] SET status = 'C' WHERE age > 45	UPDATE `users` SET `status` = "C" WHERE `docType` = "subscriber" AND `age` > 45

Delete Statements

The SQL DELETE statement is mapped to the N1QL DELETE statement as shown below:

SQL Query	N1QL Query
DELETE FROM users WHERE [Document.Id] = 'bcd001'	DELETE FROM `users` USE KEYS ["bcd001"]
DELETE FROM users WHERE status = 'inactive'	DELETE FROM `users` WHERE `status` = "inactive"

Child Table Deletes

When deleting from a child table, the SQL query is converted to an UPDATE query using an "ARRAY" expression:

SQL Query	N1QL Query
DELETE FROM users_ratings WHERE value < 0	UPDATE `users` SET `ratings` = ARRAY `value` FOR `value` IN `ratings` WHEN NOT (`value` < 0) END
DELETE FROM users_reviews WHERE score = ''	UPDATE `users` SET `reviews` = ARRAY `$child` FOR `$child` IN `reviews` WHEN NOT (`$child`.`score` = "") END

Flavor Tables Deletes

Like flavor table SELECTs, DELETEs on flavor tables always include the appropriate condition, so only docments belonging to the flavor are affected:

SQL Query	N1QL Query
DELETE FROM [users.subscriber] WHERE status = 'inactive'	DELETE FROM `users` WHERE `docType` = "subscriber" AND status = "inactive"

Example Document

/* Primary key "1" */
{
  "address" : {
    "building" : "1007",
    "coord" : [-73.856077, 40.848447],
    "street" : "Morris Park Ave",
    "zipcode" : "10462"
  },
  "borough" : "Bronx",
  "cuisine" : "Bakery",
  "grades" : [{
      "date" : "2014-03-03T00:00:00Z",
      "grade" : "A",
      "score" : 2
    }, {
      "date" : "2013-09-11T00:00:00Z",
      "grade" : "A",
      "score" : 6
    }, {
      "date" : "2013-01-24T00:00:00Z",
      "grade" : "A",
      "score" : 10
    }, {
      "date" : "2011-11-23T00:00:00Z",
      "grade" : "A",
      "score" : 9
    }, {
      "date" : "2011-03-10T00:00:00Z",
      "grade" : "B",
      "score" : 14
    }],
  "name" : "Morris Park Bake Shop",
  "restaurant_id" : "30075445"
}

Selecting Values In Objects

If the FlattenObjects property is configured to allow object flattening, then the Sync App will traverse objects and map the fields inside them as columns. For example, this query:

SELECT [address.building], [address.street] FROM restaurants

Would return this resultset:

address.building	addres.street
1007	Morris Park Ave

Selecting Values In Arrays

If the FlattenArrays property is configured to allow array flattening, then the Sync App will traverse arrays and map their individual values as columns. For example, if Flatten Arrays were set to "2", then this query:

SELECT [address.coord.0], [address.coord.1] FROM restaurants

Would return this resultset:

address.coord.0	address.coord.1
-73.856077	40.838447

Note that array flattening should only be used in cases where you know the number of array items in advance, such as with "address.coord" which will always contain two items. For arrays like "grades" which can contain arbitrary numbers of items, consider using the child tables described in Automatic Schema Discovery instead, since they will allow you to read all of the values within the array.

User-defined functions are a new feature provided by Couchbase 7 and up. They can be used with the Sync App like normal functions but with a special naming convention for using scoped functions. Normally the Sync App requires that functions already exist before they are used, to define them refer to the Couchbase documentation on CREATE FUNCTION queries. These may be run at the Couchbase console or with the Sync App in QueryPassthrough mode.

Couchbase has support for both scalar functions as well as functions that return results from subqueries. The Sync App supports scalar functions within its SQL dialect but subquery functions can only be used when QueryPassthrough is enabled. The rest of this section covers the Sync App's SQL dialect and assums that QueryPassthrough is disabled.

Global Functions

In both N1QL and Analytics mode, global user-defined functions can be accessed using either their simple names or their qualified names. The simple name is just the name of the function:

SELECT ageInYears(birthdate) FROM users

Global functions may also be invoked by qualifying them with the default namespace. Qualified names are quoted names that contain internal separators, which by default is a period though this can be changed using the DataverseSeparator property. In both N1QL and Analytics the global namespace is called Default:

SELECT [Default.ageInYears](birthdate) FROM users

Calling global functions using simple names is recommended. While the default qualfier is supported, its only intended use is for when a UDF clashes with a standard SQL function that the Sync App would otherwise translate.

Scoped Functions

Both N1QL and Analytics also allow functions to be defined outside of a global context. In Analytics functions can be attached to both dataverses and scopes which are called using two-part and three-part names respectively. In N1QL functions may only be attached to scopes so only three-part names may be used.

/* N1QL AND Analytics */
SELECT [socialNetwork.accounts.ageInYears](birthdate) FROM [socialNetwork.accounts.users]

/* Analytics only */
SELECT [socailNetwork.ageInYears](birthdate) FROM [socialNetwork.accounts.users]

The Sync App can return JSON structures as column values. The Sync App enables you to use standard SQL functions to work with these JSON structures. The examples in this section use the following array:

[
     { "grade": "A", "score": 2 },
     { "grade": "A", "score": 6 },
     { "grade": "A", "score": 10 },
     { "grade": "A", "score": 9 },
     { "grade": "B", "score": 14 }
]

JSON_EXTRACT

The JSON_EXTRACT function can extract individual values from a JSON object. The following query returns the values shown below based on the JSON path passed as the second argument to the function:

SELECT Name, JSON_EXTRACT(grades,'[0].grade') AS Grade, JSON_EXTRACT(grades,'[0].score') AS Score FROM Students;

Column Name	Example Value
Grade	A
Score	2

JSON_COUNT

The JSON_COUNT function returns the number of elements in a JSON array within a JSON object. The following query returns the number of elements specified by the JSON path passed as the second argument to the function:

SELECT Name, JSON_COUNT(grades,'[x]') AS NumberOfGrades FROM Students;

Column Name	Example Value
NumberOfGrades	5

JSON_SUM

The JSON_SUM function returns the sum of the numeric values of a JSON array within a JSON object. The following query returns the total of the values specified by the JSON path passed as the second argument to the function:

SELECT Name, JSON_SUM(score,'[x].score') AS TotalScore FROM Students;

Column Name	Example Value
TotalScore	41

JSON_MIN

The JSON_MIN function returns the lowest numeric value of a JSON array within a JSON object. The following query returns the minimum value specified by the JSON path passed as the second argument to the function:

SELECT Name, JSON_MIN(score,'[x].score') AS LowestScore FROM Students;

Column Name	Example Value
LowestScore	2

JSON_MAX

The JSON_MAX function returns the highest numeric value of a JSON array within a JSON object. The following query returns the maximum value specified by the JSON path passed as the second argument to the function:

SELECT Name, JSON_MAX(score,'[x].score') AS HighestScore FROM Students;

Column Name	Example Value
HighestScore	14

DOCUMENT

The DOCUMENT function can be used to return an document as a JSON string. DOCUMENT(*) can be used with any type of SELECT query, including queries including other columns, queries including just DOCUMENT(*), and even more complex queries like JOINs.

SELECT [Document.Id], grade, score, DOCUMENT(*) FROM grades

For example, that query would return:

Document.Id	grade	score	DOCUMENT
1	A	6	{"document.id":1,"grade":"A","score":6}
2	A	10	{"document.id":1,"grade":"A","score":10}
3	A	9	{"document.id":1,"grade":"A","score":9}
4	B	14	{"document.id":1,"grade":"B","score":14}

When used alone, DOCUMENT(*) returns the structure directly from Couchbase as if a N1QL or SQL++ SELECT * query were used. This means that no Document.Id value will be present since Couchbase does not include it automatically.

SELECT DOCUMENT(*) FROM grades

This query would return:

DOCUMENT
{"grades":{"grade":"A","score":6"}}
{"grades":{"grade":"A","score":10"}}
{"grades":{"grade":"A","score":9"}}
{"grades":{"grade":"B","score":14"}}

In addition to Automatic Schema Discovery the Sync App also allows you to statically define the schema for your Couchbase object. Schemas are defined in text-based configuration files, which makes them easy to extend. You can call the CreateSchema stored procedure to generate a schema file; see Automatic Schema Discovery for more information.

Set the Location property to the file directory that will contain the schema file. The following sections show how to extend the resulting schema or write your own.

Example Document

Let's consider the document below and extract out the nested properties as their own columns:

/* Primary key "1" */
{
  "id": 12,
  "name": "Lohia Manufacturers Inc.",
  "homeaddress": {"street": "Main "Street", "city": "Chapel Hill", "state": "NC"},
  "workaddress": {"street": "10th "Street", "city": "Chapel Hill", "state": "NC"}
  "offices": ["Chapel Hill", "London", "New York"]
  "annual_revenue": 35600000
}
/* Primary key "2" */
{
  "id": 15,
  "name": "Piago Industries",
  "homeaddress": {street": "Main Street", "city": "San Francisco", "state": "CA"},
  "workaddress": {street": "10th Street", "city": "San Francisco", "state": "CA"}
  "offices": ["Durham", "San Francisco"]
  "annual_revenue": 42600000
}

Custom Schema Definition

<rsb:info title="Customers" description="Customers" other:dataverse="" other:bucket=customers"" other:flavorexpr="" other:flavorvalue="" other:isarray="false" other:pathspec="" other:childpath="">
  <attr name="document.id"        xs:type="string"  key="true" other:iskey="true" other:pathspec=""  />
  <attr name="annual_revenue"     xs:type="integer" other:iskey="false"           other:pathspec=""  other:field="annual_revenue" />
  <attr name="homeaddress.city"   xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.city" />
  <attr name="homeaddress.state"  xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.state" />
  <attr name="homeaddress.street" xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.street" />
  <attr name="name"               xs:type="string"  other:iskey="false"           other:pathspec=""  other:field="name" />
  <attr name="id"                 xs:type="integer" other:iskey="false"           other:pathspec=""  other:field="id" />
  <attr name="offices"            xs:type="string"  other:iskey="false"           other:pathspec=""  other:field="offices" />
  <attr name="offices.0"          xs:type="string"  other:iskey="false"           other:pathspec="[" other:field="offices.0" />
  <attr name="offices.1"          xs:type="string"  other:iskey="false"           other:pathspec="[" other:field="offices.1" />
  <attr name="workaddress.city"   xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.city" />
  <attr name="workaddress.state"  xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.state" />
  <attr name="workaddress.street" xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.street" />
</rsb:info>

In Custom Schema Example, you will find the complete schema that contains the example above.

Table Properties

The schema above uses the following properties to define specific qualities for the whole table. All of them are required:

Property	Meaning
other:dataverse	The name of the dataverse the dataset belongs to. Empty if not an Analytics view.
other:bucket	The name of the bucket or dataset within Couchbase
other:flavorexpr	The URL encoded condition in a flavored table. For example, "%60docType%60%20%3D%20%22chess%22".
other:flavorvalue	The name of the flavor in a flavored table. For example, "chess".
other:isarray	Whether the table is an array child table.
other:pathspec	This is used to interpret the separators within other:childpath. See Column Properties for more details.
other:childpath	The path to the attribute that is used to UNNEST the child table. Empty if not a child table.

Column Properties

The schema above uses the following properties to define specific qualities for each column:

Property	Meaning
name	Required. The name of the column, lower-cased.
key	Used to mark the primary key. Required for Document.Id but optional for other columns.
xs:type	Required. The type of the column within the Sync App.
other:iskey	Required. Must be the same value as key, or "false" if key is not included.
other:pathspec	Required. This is used to interpret the separators within other:field.
other:field	Required. The path to the field in Couchbase.

Note that the fields which are produced by vertical flattening use the same syntax for separating array values and field values. This introduces a potential ambiguity in cases like the following, where the Sync App exposes the columns "numeric_object.0" and "array.0":

{
  "numeric_object": {
    "0": 0
  },
  "array": [
    0
  ]
}

To ensure that the Sync App can distinguish between field and array accesses, the pathspec is used to determine whether each "." in the field is an array or an object. Each "{" represents a field access, while each "[" represents an array access.

For example, with a field of "a.0.b.1" and a "pathspec" of "[{[", the N1QL expression "a[0].b[1]" would be generated. If instead the "pathspec" were "{{{", then the N1QL expression "a.`0`.b.`1`" would be generated.

This section contains a complete schema. Set the Location property to the file directory that will contain the schema file. The info section enables a relational view of a Couchbase object. For more details, see Custom Schema Definitions. The table below allows the SELECT, INSERT, UPDATE, and DELETE commands as implemented in the GET, POST, MERGE, and DELETE sections of the schema below. The operations, such as couchbaseadoSysData, are internal implementations.

<rsb:script xmlns:rsb="http://www.rssbus.com/ns/rsbscript/2">  
  <rsb:info title="Customers" description="Customers" other:dataverse="" other:bucket=customers"" other:flavorexpr="" other:flavorvalue="" other:isarray="false" other:pathspec="" other:childpath="">
    <attr name="document.id"        xs:type="string"  key="true" other:iskey="true" other:pathspec=""  />
    <attr name="annual_revenue"     xs:type="integer" other:iskey="false"           other:pathspec=""  other:field="annual_revenue" />
    <attr name="homeaddress.city"   xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.city" />
    <attr name="homeaddress.state"  xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.state" />
    <attr name="homeaddress.street" xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="homeaddress.street" />
    <attr name="name"               xs:type="string"  other:iskey="false"           other:pathspec=""  other:field="name" />
    <attr name="id"                 xs:type="integer" other:iskey="false"           other:pathspec=""  other:field="id" />
    <attr name="offices"            xs:type="string"  other:iskey="false"           other:pathspec=""  other:field="offices" />
    <attr name="offices.0"          xs:type="string"  other:iskey="false"           other:pathspec="[" other:field="offices.0" />
    <attr name="offices.1"          xs:type="string"  other:iskey="false"           other:pathspec="[" other:field="offices.1" />
    <attr name="workaddress.city"   xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.city" />
    <attr name="workaddress.state"  xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.state" />
    <attr name="workaddress.street" xs:type="string"  other:iskey="false"           other:pathspec="{" other:field="workaddress.street" />
  </rsb:info>
</rsb:script>

This section details a selection of advanced features of the Couchbase Sync App.

User Defined Views

The Sync App allows you to define virtual tables, called user defined views, whose contents are decided by a pre-configured query. These views are useful when you cannot directly control queries being issued to the drivers. See User Defined Views for an overview of creating and configuring custom views.

SSL Configuration

Use SSL Configuration to adjust how Sync App handles TLS/SSL certificate negotiations. You can choose from various certificate formats; see the SSLServerCert property under "Connection String Options" for more information.

Firewall and Proxy

Configure the Sync App for compliance with Firewall and Proxy, including Windows proxies and HTTP proxies. You can also set up tunnel connections.

Query Processing

The Sync App offloads as much of the SELECT statement processing as possible to Couchbase and then processes the rest of the query in memory (client-side).

See Query Processing for more information.

Logging

See Logging for an overview of configuration settings that can be used to refine CData logging. For basic logging, you only need to set two connection properties, but there are numerous features that support more refined logging, where you can select subsets of information to be logged using the LogModules connection property.

Customizing the SSL Configuration

By default, the Sync App attempts to negotiate SSL/TLS by checking the server's certificate against the system's trusted certificate store.

To specify another certificate, see the SSLServerCert property for the available formats to do so.

Client SSL Certificates

The Couchbase Sync App also supports setting client certificates. Set the following to connect using a client certificate.

• SSLClientCert: The name of the certificate store for the client certificate.
• SSLClientCertType: The type of key store containing the TLS/SSL client certificate.
• SSLClientCertPassword: The password for the TLS/SSL client certificate.
• SSLClientCertSubject: The subject of the TLS/SSL client certificate.

Connecting Through a Firewall or Proxy

HTTP Proxies

To connect through the Windows system proxy, you do not need to set any additional connection properties. To connect to other proxies, set ProxyAutoDetect to false.

In addition, to authenticate to an HTTP proxy, set ProxyAuthScheme, ProxyUser, and ProxyPassword, in addition to ProxyServer and ProxyPort.

Other Proxies

Set the following properties:

• To use a proxy-based firewall, set FirewallType, FirewallServer, and FirewallPort.
• To tunnel the connection, set FirewallType to TUNNEL.
• To authenticate, specify FirewallUser and FirewallPassword.
• To authenticate to a SOCKS proxy, additionally set FirewallType to SOCKS5.

Overview

Depending upon the connection settings being used, the Sync App can present several different mappings between Couchbase entities and relational tables and views. For more details on each of these capabilities, refer to the NoSQL portion of this documentation.

• When connecting to the N1QL query service, the Sync App models Couchbase buckets as relational tables. In addition, if TypeDetectionScheme is set to DocType or Infer, the Sync App will present different document flavors in each bucket as their own tables.
• When connecting to the Analytics service, the Sync App models Couchbase datasets as relational views.
• When connecting with either service, the Sync App can expose arrays of data as child tables or views.

Please see the Automatic Schema Discovery section for more details on how flavor and child tables are exposed. In addition, the NewChildJoinsMode connection property is recommended for workflows that make heavy use of child tables. The documentation for that connection property details the improvements it makes to the Sync App data model.

Dataverses, Scopes and Collections

Couchbase has different ways of grouping buckets and datasets depending on the CouchbaseService and version of Couchbase you are connecting to:

• Couchbase organizes Analytics datsets into groups called dataverses. By default the Sync App exposes datasets from all dataverses using compound names like Default.users as described in DataverseSeparator. It is important to remember that these compound names must be quoted when used in queries, for example SELECT * FROM [Default.users]
• You may also set the Dataverse property to limit the the Sync App to exposing a single dataverse. This disables compound names so view names will not include the dataset.
• When connecting to Couchbase 7 and above, the Sync App will use the scope, collection and bucket/dataset name to build table and view names. For example, a table with a name like crm.accounts.customers exposes the customers collection under the accounts scope of the crm bucket. These must be quoted the same as other compound names when used in queries, for example SELECT * FROM [crm.accounts.customers]

Live Metadata

All of the schemas provided by the Sync App are dynamically retrieved from Couchbase, so any changes in the buckets or fields within Couchbase will be reflected in the Sync App the next time you connect. You may also issue a reset query to refresh schemas without having to close the connection:

RESET SCHEMA CACHE

The connection string properties are the various options that can be used to establish a connection. This section provides a complete list of the options you can configure in the connection string for this provider. Click the links for further details.

For more information on establishing a connection, see Establishing a Connection.

Authentication

---

Property	Description
AuthScheme	The type of authentication to use when connecting to Couchbase.
User	The Couchbase user account used to authenticate.
Password	The password used to authenticate the user.
CredentialsFile	Use this property if you need to provide credentials for multiple users or buckets. This file takes priority over other forms of authentication.
Server	The address of the Couchbase server or servers to which you are connecting.
CouchbaseService	Determines the Couchbase service to connect to. Default is N1QL. Available options are N1QL and Analytics.
ConnectionMode	Determines how to connect to the Couchbase server. Must be either Direct or Cloud.
DNSServer	Determines what DNS server to use when retrieving Couchbase Capella information.
N1QLPort	The port for connecting to the Couchbase N1QL Endpoint.
AnalyticsPort	The port for connecting to the Couchbase Analytics Endpoint.
WebConsolePort	The port for connecting to the Couchbase Web Console.

SSL

---

Property	Description
SSLClientCert	The TLS/SSL client certificate store for SSL Client Authentication (2-way SSL).
SSLClientCertType	The type of key store containing the TLS/SSL client certificate.
SSLClientCertPassword	The password for the TLS/SSL client certificate.
SSLClientCertSubject	The subject of the TLS/SSL client certificate.
UseSSL	Whether to negotiate TLS/SSL when connecting to the Couchbase server.
SSLServerCert	The certificate to be accepted from the server when connecting using TLS/SSL.

Firewall

---

Property	Description
FirewallType	The protocol used by a proxy-based firewall.
FirewallServer	The name or IP address of a proxy-based firewall.
FirewallPort	The TCP port for a proxy-based firewall.
FirewallUser	The user name to use to authenticate with a proxy-based firewall.
FirewallPassword	A password used to authenticate to a proxy-based firewall.

Proxy

---

Property	Description
ProxyAutoDetect	This indicates whether to use the system proxy settings or not. This takes precedence over other proxy settings, so you'll need to set ProxyAutoDetect to FALSE in order use custom proxy settings.
ProxyServer	The hostname or IP address of a proxy to route HTTP traffic through.
ProxyPort	The TCP port the ProxyServer proxy is running on.
ProxyAuthScheme	The authentication type to use to authenticate to the ProxyServer proxy.
ProxyUser	A user name to be used to authenticate to the ProxyServer proxy.
ProxyPassword	A password to be used to authenticate to the ProxyServer proxy.
ProxySSLType	The SSL type to use when connecting to the ProxyServer proxy.
ProxyExceptions	A semicolon separated list of destination hostnames or IPs that are exempt from connecting through the ProxyServer .

Logging

---

Property	Description
LogModules	Core modules to be included in the log file.

Schema

---

Property	Description
Location	A path to the directory that contains the schema files defining tables, views, and stored procedures.
BrowsableSchemas	This property restricts the schemas reported to a subset of the available schemas. For example, BrowsableSchemas=SchemaA,SchemaB,SchemaC.
Tables	This property restricts the tables reported to a subset of the available tables. For example, Tables=TableA,TableB,TableC.
Views	Restricts the views reported to a subset of the available tables. For example, Views=ViewA,ViewB,ViewC.
Dataverse	Which Analytics dataverse to scan when discovering tables.
TypeDetectionScheme	Determines how the provider builds tables and columns from the buckets found in Couchbase.
InferNumSampleValues	The maximum number of values for every field to scan before determining its data type. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
InferSampleSize	The maximum number of documents to scan for the columns available in the bucket. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
InferSimilarityMetric	Specifies the similarity degree where different schemas will be considered to be the same flavor. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
FlexibleSchemas	Whether the provider allows queries to use columns that it has not discovered.
ExposeTTL	Specifies whether document TTL information should be exposed.
NumericStrings	Whether to allow string values to be treated as numbers.
IgnoreChildAggregates	Whether the provider exposes aggregate columns that are also available as child tables. Ignored if TableSupport is not set to Full.
TableSupport	How much effort the provider will put into discovering tables on the Couchbase server.
NewChildJoinsMode	Determines the kind of child table model the provider exposes.

Miscellaneous

---

Property	Description
AllowJSONParameters	Allows raw JSON to be used in parameters when QueryPassthrough is enabled.
ChildSeparator	The character or characters used to denote child tables.
CreateTableRamQuota	The default RAM quota, in megabytes, to use when inserting buckets via the CREATE TABLE syntax.
DataverseSeparator	The character or characters used to denote Analytics dataverses and scopes/collections.
FlattenArrays	The number of elements to expose as columns from nested arrays. Ignored if IgnoreChildAggregates is enabled.
FlattenObjects	Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON.
FlavorSeparator	The character or characters used to denote flavors.
GenerateSchemaFiles	Indicates the user preference as to when schemas should be generated and saved.
InsertNullValues	Determines whether an INSERT should include fields that have NULL values.
MaxRows	Limits the number of rows returned rows when no aggregation or group by is used in the query. This helps avoid performance issues at design time.
Other	These hidden properties are used only in specific use cases.
Pagesize	The maximum number of results to return per page from Couchbase.
PeriodsSeparator	The character or characters used to denote hierarchy.
PseudoColumns	This property indicates whether or not to include pseudo columns as columns to the table.
QueryExecutionTimeout	This sets the server-side timeout for the query, which governs how long Couchbase will execute the query before returning a timeout error.
QueryPassthrough	This option passes the query to the Couchbase server as is.
RowScanDepth	The maximum number of rows to scan to look for the columns available in a table.
StrictComparison	Adjusts how precisely to translate filters on SQL input queries into Couchbase queries. This can be set to a comma-separated list of values, where each value can be one of: date, number, boolean, or string.
Timeout	The value in seconds until the timeout error is thrown, canceling the operation.
TransactionDurability	Specifies how a document must be stored for a transaction to succeed. Specifies whether to use N1QL transactions when executing queries.
TransactionTimeout	This sets the amount of time a transaction may execute before it is timed out by Couchbase.
UpdateNullValues	Determines whether an UPDATE writes NULL values as NULL, or removes them.
UseCollectionsForDDL	Whether to assume that CREATE TABLE statements use collections instead of flavors. Only takes effect when connecting to Couchbase v7+ and GenerateSchemaFiles is set to OnCreate.
UserDefinedViews	A filepath pointing to the JSON configuration file containing your custom views.
UseTransactions	Specifies whether to use N1QL transactions when executing queries.
ValidateJSONParameters	Allows the provider to validate that string parameters are valid JSON before sending the query to Couchbase.

This section provides a complete list of the Authentication properties you can configure in the connection string for this provider.

---

Property	Description
AuthScheme	The type of authentication to use when connecting to Couchbase.
User	The Couchbase user account used to authenticate.
Password	The password used to authenticate the user.
CredentialsFile	Use this property if you need to provide credentials for multiple users or buckets. This file takes priority over other forms of authentication.
Server	The address of the Couchbase server or servers to which you are connecting.
CouchbaseService	Determines the Couchbase service to connect to. Default is N1QL. Available options are N1QL and Analytics.
ConnectionMode	Determines how to connect to the Couchbase server. Must be either Direct or Cloud.
DNSServer	Determines what DNS server to use when retrieving Couchbase Capella information.
N1QLPort	The port for connecting to the Couchbase N1QL Endpoint.
AnalyticsPort	The port for connecting to the Couchbase Analytics Endpoint.
WebConsolePort	The port for connecting to the Couchbase Web Console.

The type of authentication to use when connecting to Couchbase.

Remarks

• Auto: This option is deprecated and included only for compatibility.
• Basic: Uses HTTP Basic authentication with User and Password.
• CredentialsFile: Uses a credentials file. This will require that the CredentialsFile property be set.
• SSLCertificate: Uses SSL client certificate authentication. Requires that UseSSL be enabled and that SSLClientCert and SSLClientCertType be set.

Note that only Basic authentication is supported when using the "Cloud" ConnectionMode.

The Couchbase user account used to authenticate.

Remarks

Together with Password, this field is used to authenticate against the Couchbase server.

The password used to authenticate the user.

Remarks

The User and Password are together used to authenticate with the server.

Use this property if you need to provide credentials for multiple users or buckets. This file takes priority over other forms of authentication.

Remarks

Use this property if you need to provide credentials for multiple users or buckets. This takes priority over other forms of authentication.

Set CredentialsFile to the path to a file that has the same markup as below:

[{"user": "YourUserName1", "pass":"YourPassword1"},
  {"user": "YourUserName2", "pass":"YourPassword2"}] 

The address of the Couchbase server or servers to which you are connecting.

Remarks

This value can be set to a hostname or an IP address, like "couchbase-server.com" or "1.2.3.4". It can also be set to an HTTP or HTTPS URL, such as "https://couchbase-server.com" or "http://1.2.3.4". If ConnectionMode is set to Cloud then this should be the hostname of the Couchbase Cloud instance as reported in the control panel.

If the URL form is used, then setting this option will also set the UseSSL option: if the URL scheme is "https://", then UseSSL will be set to true, and a URL with "http://" will set UseSSL to false.

A port value cannot be used as part of this option, so values like "http://couchbase-server.com:8093" are not allowed. Please use WebConsolePort, N1QLPort and AnalyticsPort.

This value can also accept multiple servers in the above format separated by commas, such as "1.2.3.4, couchbase-server.com". This will allow the Sync App to recover the connection in case some of the servers listed are inaccessible.

Note that while the Sync App will try to recover the connection as a whole, it may lose individual operations. For example, while a long-running query will fail if the server becomes inaccesssible while that query is running, that query can be retried on the same connection and the Sync App will execute it on the next active server.

Determines the Couchbase service to connect to. Default is N1QL. Available options are N1QL and Analytics.

Remarks

Determines the Couchbase service to connect to. Default is N1QL. Available options are N1QL and Analytics

Determines how to connect to the Couchbase server. Must be either Direct or Cloud.

Remarks

By default the Sync App connects to Couchbase directly using the address given in the Server option. The Server must be running the appropriate CouchbaseService to accept the connection. This will work in most on-premise or basic cloud deployments.

This should be set to Cloud when connecting to Couchbase Capella or a custom deployment that uses service records. These records will allow the Sync App to determine the exact Couchbase servers that provide the appropriate CouchbaseService. You must also set the DNSServer property so that the Sync App is able to fetch these service records.

Note that enabling Cloud mode will override these connection properties with the values discovered by contacting the cluster:

• Server
• N1QLPort
• AnalyticsPort

Determines what DNS server to use when retrieving Couchbase Capella information.

Remarks

In most cases any public DNS server can be provided here such as the ones provided by OpenDNS, Cloudflare or Google.

If these are not accessible then you will need to use the DNS server configured by your network administrator.

The port for connecting to the Couchbase N1QL Endpoint.

Remarks

This defaults to 8093 when not using SSL, and 18093 when using SSL. See UseSSL.

This port is used for submitting queries when CouchbaseService is set to N1QL. Any requests to manage indices will also go through this port.

The port for connecting to the Couchbase Analytics Endpoint.

Remarks

This defaults to 8095 when not using SSL, and 18095 when using SSL. See UseSSL.

This port is used for submitting queries when CouchbaseService is set to Analytics.

The port for connecting to the Couchbase Web Console.

Remarks

This defaults to 8091 when not using SSL, and 18091 when using SSL. See UseSSL.

This port is used for API operations like managing buckets.

This section provides a complete list of the SSL properties you can configure in the connection string for this provider.

---

Property	Description
SSLClientCert	The TLS/SSL client certificate store for SSL Client Authentication (2-way SSL).
SSLClientCertType	The type of key store containing the TLS/SSL client certificate.
SSLClientCertPassword	The password for the TLS/SSL client certificate.
SSLClientCertSubject	The subject of the TLS/SSL client certificate.
UseSSL	Whether to negotiate TLS/SSL when connecting to the Couchbase server.
SSLServerCert	The certificate to be accepted from the server when connecting using TLS/SSL.

The TLS/SSL client certificate store for SSL Client Authentication (2-way SSL).

Remarks

The name of the certificate store for the client certificate.

The SSLClientCertType field specifies the type of the certificate store specified by SSLClientCert. If the store is password protected, specify the password in SSLClientCertPassword.

SSLClientCert is used in conjunction with the SSLClientCertSubject field in order to specify client certificates. If SSLClientCert has a value, and SSLClientCertSubject is set, a search for a certificate is initiated. See SSLClientCertSubject for more information.

Designations of certificate stores are platform-dependent.

The following are designations of the most common User and Machine certificate stores in Windows:

MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.
SPC	Software publisher certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (for example, PKCS12 certificate store).

The type of key store containing the TLS/SSL client certificate.

Remarks

This property can take one of the following values:

USER - default	For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note that this store type is not available in Java.
MACHINE	For Windows, this specifies that the certificate store is a machine store. Note that this store type is not available in Java.
PFXFILE	The certificate store is the name of a PFX (PKCS12) file containing certificates.
PFXBLOB	The certificate store is a string (base-64-encoded) representing a certificate store in PFX (PKCS12) format.
JKSFILE	The certificate store is the name of a Java key store (JKS) file containing certificates. Note that this store type is only available in Java.
JKSBLOB	The certificate store is a string (base-64-encoded) representing a certificate store in JKS format. Note that this store type is only available in Java.
PEMKEY_FILE	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
PEMKEY_BLOB	The certificate store is a string (base64-encoded) that contains a private key and an optional certificate.
PUBLIC_KEY_FILE	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
PUBLIC_KEY_BLOB	The certificate store is a string (base-64-encoded) that contains a PEM- or DER-encoded public key certificate.
SSHPUBLIC_KEY_FILE	The certificate store is the name of a file that contains an SSH-style public key.
SSHPUBLIC_KEY_BLOB	The certificate store is a string (base-64-encoded) that contains an SSH-style public key.
P7BFILE	The certificate store is the name of a PKCS7 file containing certificates.
PPKFILE	The certificate store is the name of a file that contains a PuTTY Private Key (PPK).
XMLFILE	The certificate store is the name of a file that contains a certificate in XML format.
XMLBLOB	The certificate store is a string that contains a certificate in XML format.

The password for the TLS/SSL client certificate.

Remarks

If the certificate store is of a type that requires a password, this property is used to specify that password to open the certificate store.

The subject of the TLS/SSL client certificate.

Remarks

When loading a certificate the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property. If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks the first certificate in the certificate store.

The certificate subject is a comma separated list of distinguished name fields and values. For example, "CN=www.server.com, OU=test, C=US, [email protected]". The common fields and their meanings are shown below.

Field	Meaning
CN	Common Name. This is commonly a host name like www.server.com.
O	Organization
OU	Organizational Unit
L	Locality
S	State
C	Country
E	Email Address

If a field value contains a comma, it must be quoted.

Whether to negotiate TLS/SSL when connecting to the Couchbase server.

Remarks

When this is set to true, the defaults for the following options change:

Property	Plaintext Default	SSL Default
AnalyticsPort	8095	18095
N1QLPort	8093	18093
WebConsolePort	8091	18091

This option should be enabled when connecting to Couchbase Capella because all Capella deployments use SSL by default.

The certificate to be accepted from the server when connecting using TLS/SSL.

Remarks

If using a TLS/SSL connection, this property can be used to specify the TLS/SSL certificate to be accepted from the server. Any other certificate that is not trusted by the machine is rejected.

This property can take the following forms:

Description	Example
A full PEM Certificate (example shortened for brevity)	-----BEGIN CERTIFICATE----- MIIChTCCAe4CAQAwDQYJKoZIhv......Qw== -----END CERTIFICATE-----
A path to a local file containing the certificate	C:\cert.cer
The public key (example shortened for brevity)	-----BEGIN RSA PUBLIC KEY----- MIGfMA0GCSq......AQAB -----END RSA PUBLIC KEY-----
The MD5 Thumbprint (hex values can also be either space or colon separated)	ecadbdda5a1529c58a1e9e09828d70e4
The SHA1 Thumbprint (hex values can also be either space or colon separated)	34a929226ae0819f2ec14b4a3d904f801cbb150d

If not specified, any certificate trusted by the machine is accepted.

Use '*' to signify to accept all certificates. Note that this is not recommended due to security concerns.

This section provides a complete list of the Firewall properties you can configure in the connection string for this provider.

---

Property	Description
FirewallType	The protocol used by a proxy-based firewall.
FirewallServer	The name or IP address of a proxy-based firewall.
FirewallPort	The TCP port for a proxy-based firewall.
FirewallUser	The user name to use to authenticate with a proxy-based firewall.
FirewallPassword	A password used to authenticate to a proxy-based firewall.

The protocol used by a proxy-based firewall.

Remarks

This property specifies the protocol that the Sync App will use to tunnel traffic through the FirewallServer proxy. Note that by default, the Sync App connects to the system proxy; to disable this behavior and connect to one of the following proxy types, set ProxyAutoDetect to false.

Type	Default Port	Description
TUNNEL	80	When this is set, the Sync App opens a connection to Couchbase and traffic flows back and forth through the proxy.
SOCKS4	1080	When this is set, the Sync App sends data through the SOCKS 4 proxy specified by FirewallServer and FirewallPort and passes the FirewallUser value to the proxy, which determines if the connection request should be granted.
SOCKS5	1080	When this is set, the Sync App sends data through the SOCKS 5 proxy specified by FirewallServer and FirewallPort. If your proxy requires authentication, set FirewallUser and FirewallPassword to credentials the proxy recognizes.

To connect to HTTP proxies, use ProxyServer and ProxyPort. To authenticate to HTTP proxies, use ProxyAuthScheme, ProxyUser, and ProxyPassword.

The name or IP address of a proxy-based firewall.

Remarks

This property specifies the IP address, DNS name, or host name of a proxy allowing traversal of a firewall. The protocol is specified by FirewallType: Use FirewallServer with this property to connect through SOCKS or do tunneling. Use ProxyServer to connect to an HTTP proxy.

Note that the Sync App uses the system proxy by default. To use a different proxy, set ProxyAutoDetect to false.

The TCP port for a proxy-based firewall.

Remarks

This specifies the TCP port for a proxy allowing traversal of a firewall. Use FirewallServer to specify the name or IP address. Specify the protocol with FirewallType.

The user name to use to authenticate with a proxy-based firewall.

Remarks

The FirewallUser and FirewallPassword properties are used to authenticate against the proxy specified in FirewallServer and FirewallPort, following the authentication method specified in FirewallType.

A password used to authenticate to a proxy-based firewall.

Remarks

This property is passed to the proxy specified by FirewallServer and FirewallPort, following the authentication method specified by FirewallType.

This section provides a complete list of the Proxy properties you can configure in the connection string for this provider.

---

Property	Description
ProxyAutoDetect	This indicates whether to use the system proxy settings or not. This takes precedence over other proxy settings, so you'll need to set ProxyAutoDetect to FALSE in order use custom proxy settings.
ProxyServer	The hostname or IP address of a proxy to route HTTP traffic through.
ProxyPort	The TCP port the ProxyServer proxy is running on.
ProxyAuthScheme	The authentication type to use to authenticate to the ProxyServer proxy.
ProxyUser	A user name to be used to authenticate to the ProxyServer proxy.
ProxyPassword	A password to be used to authenticate to the ProxyServer proxy.
ProxySSLType	The SSL type to use when connecting to the ProxyServer proxy.
ProxyExceptions	A semicolon separated list of destination hostnames or IPs that are exempt from connecting through the ProxyServer .

This indicates whether to use the system proxy settings or not. This takes precedence over other proxy settings, so you'll need to set ProxyAutoDetect to FALSE in order use custom proxy settings.

Remarks

This takes precedence over other proxy settings, so you'll need to set ProxyAutoDetect to FALSE in order use custom proxy settings.

To connect to an HTTP proxy, see ProxyServer. For other proxies, such as SOCKS or tunneling, see FirewallType.

The hostname or IP address of a proxy to route HTTP traffic through.

Remarks

The hostname or IP address of a proxy to route HTTP traffic through. The Sync App can use the HTTP, Windows (NTLM), or Kerberos authentication types to authenticate to an HTTP proxy.

If you need to connect through a SOCKS proxy or tunnel the connection, see FirewallType.

By default, the Sync App uses the system proxy. If you need to use another proxy, set ProxyAutoDetect to false.

The TCP port the ProxyServer proxy is running on.

Remarks

The port the HTTP proxy is running on that you want to redirect HTTP traffic through. Specify the HTTP proxy in ProxyServer. For other proxy types, see FirewallType.

The authentication type to use to authenticate to the ProxyServer proxy.

Remarks

This value specifies the authentication type to use to authenticate to the HTTP proxy specified by ProxyServer and ProxyPort.

Note that the Sync App will use the system proxy settings by default, without further configuration needed; if you want to connect to another proxy, you will need to set ProxyAutoDetect to false, in addition to ProxyServer and ProxyPort. To authenticate, set ProxyAuthScheme and set ProxyUser and ProxyPassword, if needed.

The authentication type can be one of the following:

• BASIC: The Sync App performs HTTP BASIC authentication.
• DIGEST: The Sync App performs HTTP DIGEST authentication.
• NEGOTIATE: The Sync App retrieves an NTLM or Kerberos token based on the applicable protocol for authentication.
• PROPRIETARY: The Sync App does not generate an NTLM or Kerberos token. You must supply this token in the Authorization header of the HTTP request.

If you need to use another authentication type, such as SOCKS 5 authentication, see FirewallType.

A user name to be used to authenticate to the ProxyServer proxy.

Remarks

The ProxyUser and ProxyPassword options are used to connect and authenticate against the HTTP proxy specified in ProxyServer.

You can select one of the available authentication types in ProxyAuthScheme. If you are using HTTP authentication, set this to the user name of a user recognized by the HTTP proxy. If you are using Windows or Kerberos authentication, set this property to a user name in one of the following formats:

user@domain
domain\user

A password to be used to authenticate to the ProxyServer proxy.

Remarks

This property is used to authenticate to an HTTP proxy server that supports NTLM (Windows), Kerberos, or HTTP authentication. To specify the HTTP proxy, you can set ProxyServer and ProxyPort. To specify the authentication type, set ProxyAuthScheme.

If you are using HTTP authentication, additionally set ProxyUser and ProxyPassword to HTTP proxy.

If you are using NTLM authentication, set ProxyUser and ProxyPassword to your Windows password. You may also need these to complete Kerberos authentication.

For SOCKS 5 authentication or tunneling, see FirewallType.

By default, the Sync App uses the system proxy. If you want to connect to another proxy, set ProxyAutoDetect to false.

The SSL type to use when connecting to the ProxyServer proxy.

Remarks

This property determines when to use SSL for the connection to an HTTP proxy specified by ProxyServer. This value can be AUTO, ALWAYS, NEVER, or TUNNEL. The applicable values are the following:

AUTO	Default setting. If the URL is an HTTPS URL, the Sync App will use the TUNNEL option. If the URL is an HTTP URL, the component will use the NEVER option.
ALWAYS	The connection is always SSL enabled.
NEVER	The connection is not SSL enabled.
TUNNEL	The connection is through a tunneling proxy. The proxy server opens a connection to the remote host and traffic flows back and forth through the proxy.

A semicolon separated list of destination hostnames or IPs that are exempt from connecting through the ProxyServer .

Remarks

The ProxyServer is used for all addresses, except for addresses defined in this property. Use semicolons to separate entries.

Note that the Sync App uses the system proxy settings by default, without further configuration needed; if you want to explicitly configure proxy exceptions for this connection, you need to set ProxyAutoDetect = false, and configure ProxyServer and ProxyPort. To authenticate, set ProxyAuthScheme and set ProxyUser and ProxyPassword, if needed.

This section provides a complete list of the Logging properties you can configure in the connection string for this provider.

---

Property	Description
LogModules	Core modules to be included in the log file.

Core modules to be included in the log file.

Remarks

Only the modules specified (separated by ';') will be included in the log file. By default all modules are included.

See the Logging page for an overview.

This section provides a complete list of the Schema properties you can configure in the connection string for this provider.

---

Property	Description
Location	A path to the directory that contains the schema files defining tables, views, and stored procedures.
BrowsableSchemas	This property restricts the schemas reported to a subset of the available schemas. For example, BrowsableSchemas=SchemaA,SchemaB,SchemaC.
Tables	This property restricts the tables reported to a subset of the available tables. For example, Tables=TableA,TableB,TableC.
Views	Restricts the views reported to a subset of the available tables. For example, Views=ViewA,ViewB,ViewC.
Dataverse	Which Analytics dataverse to scan when discovering tables.
TypeDetectionScheme	Determines how the provider builds tables and columns from the buckets found in Couchbase.
InferNumSampleValues	The maximum number of values for every field to scan before determining its data type. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
InferSampleSize	The maximum number of documents to scan for the columns available in the bucket. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
InferSimilarityMetric	Specifies the similarity degree where different schemas will be considered to be the same flavor. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.
FlexibleSchemas	Whether the provider allows queries to use columns that it has not discovered.
ExposeTTL	Specifies whether document TTL information should be exposed.
NumericStrings	Whether to allow string values to be treated as numbers.
IgnoreChildAggregates	Whether the provider exposes aggregate columns that are also available as child tables. Ignored if TableSupport is not set to Full.
TableSupport	How much effort the provider will put into discovering tables on the Couchbase server.
NewChildJoinsMode	Determines the kind of child table model the provider exposes.

A path to the directory that contains the schema files defining tables, views, and stored procedures.

Remarks

The path to a directory which contains the schema files for the Sync App (.rsd files for tables and views, .rsb files for stored procedures). The folder location can be a relative path from the location of the executable. The Location property is only needed if you want to customize definitions (for example, change a column name, ignore a column, and so on) or extend the data model with new tables, views, or stored procedures.

If left unspecified, the default location is "%APPDATA%\\CData\\Couchbase Data Provider\\Schema" with %APPDATA% being set to the user's configuration directory:

This property restricts the schemas reported to a subset of the available schemas. For example, BrowsableSchemas=SchemaA,SchemaB,SchemaC.

Remarks

Listing the schemas from databases can be expensive. Providing a list of schemas in the connection string improves the performance.

This property restricts the tables reported to a subset of the available tables. For example, Tables=TableA,TableB,TableC.

Remarks

Listing the tables from some databases can be expensive. Providing a list of tables in the connection string improves the performance of the Sync App.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the tables you want in a comma-separated list. Each table should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Tables=TableA,[TableB/WithSlash],WithCatalog.WithSchema.`TableC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

Restricts the views reported to a subset of the available tables. For example, Views=ViewA,ViewB,ViewC.

Remarks

Listing the views from some databases can be expensive. Providing a list of views in the connection string improves the performance of the Sync App.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the views you want in a comma-separated list. Each view should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Views=ViewA,[ViewB/WithSlash],WithCatalog.WithSchema.`ViewC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

Which Analytics dataverse to scan when discovering tables.

Remarks

This property is empty by default, which means that all dataverses will be scanned and table names will be generated as described in DataverseSeparator.

If you assign this property to a non-blank value, then the Sync App will scan only the corresponding dataverse (for example, setting this to "Default" scans the Default dataverse). Since only one dataverse is being scanned, table names will not be prefixed with the dataverse name. It is recommended to set this property to "Default" if you are coming from a previous version of the Sync App and need backwards compatability.

If you are connecting to Couchbase 7.0 or later, this option will be treated as a compound name containing both a dataset and a scope. For example, if you have previously created collections like these:

CREATE ANALYTICS SCOPE websites.exampledotcom
CREATE ANALYTICS COLLECTION websites.exampledotcom.traffic ON examplecom_traffic_bucket
CREATE ANALYTICS COLLECTION websites.exampledotcom.ads ON examplecom_ads_bucket

You would set this option to "websites.exampledotcom".

Determines how the provider builds tables and columns from the buckets found in Couchbase.

Remarks

A comma-separated list of the following options:

DocType	This discovers tables by checking at each bucket and looking for different values of the "docType" field in the documents. For example, if the bucket beer-sample contains documents with "docType" = 'brewery' and "docType" = 'beer', this will generate three tables: beer-sample (containing all documents), beer-sample.brewery (containing just breweries) and beer-sample.beer (containing just beers). Like RowScan, this will scan a sample of the documents in each flavor and determine the data type for each field. RowScanDepth determines how many documents are scanned from each flavor.
DocType=fieldName	Like DocType, but this scans based off of a field called "fieldName" rather than "docType". "fieldName" must match the field name in Couchbase exactly, including case.
Infer	This uses the N1QL INFER statement to determine what tables and columns exist. This does more flexible flavor detection than DocType, but is only available for Couchbase Enterprise.
RowScan	This reads a sample of documents from a bucket, and heuristically determines the data type. RowScanDepth determines how many documents are scanned. It does not do any flavor detection.
None	This is like RowScan, but will always return columns that have string types instead of the detected type.

The maximum number of values for every field to scan before determining its data type. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.

Remarks

The maximum number of values to scan from every field of the sampled documents before determining the field's data type. This property enables additional configuration of Automatic Schema Discovery when you are using the Couchbase Infer command -- TypeDetectionScheme must also be set to Infer to use this propery.

The maximum number of documents to scan for the columns available in the bucket. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.

Remarks

The maximum number of documents to scan for the columns available in the bucket. The Infer command will return column metadata by scanning a random sample of documents of the size specified here.

Setting a high value may decrease performance. Setting a low value may prevent the column and data type from being determined properly, especially when there is null data.

This property enables additional configuration of Automatic Schema Discovery when you are using the Couchbase Infer command -- TypeDetectionScheme must also be set to Infer to use this propery.

Specifies the similarity degree where different schemas will be considered to be the same flavor. Applies to Automatic Schema Discovery when TypeDetectionScheme is set to INFER.

Remarks

This property specifies how similar two schemas must be to be considered to be the same flavor. As an example, consider the following rows:

Row 1: ColA, ColB, ColC, ColD
Row 2: ColA, ColB, ColE, ColF
Row 3: ColB, ColF, ColX, ColY

You can configure the columns returned for each flavor with different InferSimilarityMetric values, as in the following examples:

• If you set InferSimilarityMetric to 1, the Sync App will return no flavors.
• If you set InferSimilarityMetric to 0.5, the Sync App will return 2 flavors, Row1 and Row2 making up one, and Row3 making up another.
• If you set InferSimilarityMetric to 0.25, the Sync App will return a single flavor containing all rows.

You can then query document flavors using dot notation, as in the following statement:

SELECT * FROM [Items.Technology]

This property enables additional configuration of Automatic Schema Discovery when you are using the Couchbase Infer command -- TypeDetectionScheme must also be set to Infer to use this propery.

Whether the provider allows queries to use columns that it has not discovered.

Remarks

By default Sync App will only allow queries to use columns that it has found during the metadata discovery process (see TypeDetectionScheme for details). This means that the Sync App has the full information for each column it presents, but it also means that fields set on only a few documents may not be exposed. Disabling this option means that the Sync App will allow you to write a query with any columns you want. If you use columns in a query that have not been discovered the Sync App will assume that they are simple strings.

For example, the Sync App uses column type information to automatically convert dates for comparision since Couchbase cannot natively compare dates directly. If the Sync App detects that datecol is a date field, it can apply the STR_TO_MILLIS conversion automatically:

/* SQL */
WHERE datecol < '2020-06-12';

/* N1QL */
WHERE STR_TO_MILLIS(datecol) < STR_TO_MILLIS('2020-06-12');

When using undiscovered columns the Sync App cannot make this type of conversion for you. You must apply any needed conversions manually to ensure that operations behave the way you want them to.

Specifies whether document TTL information should be exposed.

Remarks

By default the Sync App does not expose TTL values or consider document TTLs when performing DML operations. Enabling this option exposes TTL values in two ways:

• All tables get a new column called Document.Expiration which contains the TTL value for each document. This column is an integer and returns whatever TTL value is stored in Couchbase directly. This column is read-write on bucket tables and read-only on child tables.
• INSERT and UPDATE will use this field to set TTL values, or to preserve them (for update) when none is provided. Setting the field to either 0 or NULL will remove the TTL from any affected documents.

Note that enabling this features requires that your server be version 6.5.1 or later and that your CouchbaseService is set to N1QL. If either of these is not the case the Sync App will not connect.

Whether to allow string values to be treated as numbers.

Remarks

By default this property is enabled and the Sync App will treat string values as numeric if they all the values it samples during schema detection are numeric. This can cause type errors later on if the field contains non-numeric values in other documents. If this property is disabled then numeric strings are left as strings although other string-based data types like timestamps will still be detected.

For example, the "code" field in the below bucket would be affected by this setting. By default it would be considered an integer but if this property were enabled it would be treated as a string.

{ "code": "123", "message": "Please restart your computer" }
{ "code": "456", "message": "Urgent update must be applied" }

Whether the provider exposes aggregate columns that are also available as child tables. Ignored if TableSupport is not set to Full.

Remarks

The Sync App will expose array fields within a bucket as a separate child table, such as in the Games_scores example described in Automatic Schema Discovery. By default the Sync App will also expose these array fields as JSON aggregates on the base table. For example, either of these queries would return information on game scores:

/* Return each score as an individual row */ 
SELECT value FROM Games_scores;

/* Return all scores for each Game as a JSON string */
SELECT scores FROM Games;

Since these aggregates are exposed on the base table, they will be generated even when the information they contain is redundant. For example, when performing this join the scores aggregate on Games is populated as well as the value column on Games_scores. Internally this causes two copies of the scores data to be transferred from Couchbase.

/* Retrieves score data twice, once for Games.scores and once for Games_scores.value */
SELECT * FROM Games INNER JOIN Games_scores ON Games.[Document.Id] = Games_scores.[Document.Id]

This option can be used to prevent the aggregate field from being exposed when the same information is also available from a child table. In the games example, setting this option to true means that the Games table would only expose a primary key column. The only way to retrieve information about scores would be the child table, so score data would only be read once from Couchbase.

/* Only exposes Document.Id, not scores */
SELECT * FROM Games;

/* Only retrieves score data once for Games_scores.value */
SELECT * FROM Games INNER JOIN Games_scores ON Games.[Document.Id] = Games_scores.[Document.Id]

Note that this option overrides FlattenArrays, since all data from flattened arrays is also avaialable as child tables. If this option is set then no array flattening is performed, even if FlattenArrays is set to a value over 0.

How much effort the provider will put into discovering tables on the Couchbase server.

Remarks

The available options are:

Full	The Sync App will discover the available buckets, and look inside of each of those buckets for child tables. This provides the most flexible way to access nested data, but requires that each bucket on your server have primary indexes.
Basic	The Sync App will discover the available buckets, but will not look inside of them for child tables. This is recommended for cases where you either want to reduce the time that schema detection takes, or if your buckets do not have primary indexes.
None	The Sync App will only use the schema files found in the Location directory, and will not discover buckets on the server. This option should only be used after you have already created schema files. Using this option without schema files will result in no tables being available.

Determines the kind of child table model the provider exposes.

Remarks

By default the Sync App exposes a backwards-compatible data model that is not fully relational. In this mode non-child tables have a primary key called Document.Id, but child tables do not have a primary key. Instead they have a column called Document.Id which has the same value as the Document.Id of the parent row that contains the child row.

For example, a parent table invoices containing invoice records may look like this:

Document.Id	customer
1	Adam
2	Beatrice
3	Charlie

And its child invoices_lineitems containing line items may look like this:

Document.Id	item
1	laptop
1	keyboard
2	stapler
3	whiteboard
3	markers

This model has several limitations:

• Complex JOIN results may be incorrect. In most cases the Sync App can translate a JOIN like SELECT * FROM invoices INNERT JOIN invoices_lineitems ON invoices.[Document.Id] = invoices_lineitems.[Document.Id] into an UNNEST. But if the JOIN is too complex then both sides are executed separately which can produce incorrect results.
• DML operations on nested child tables are impossible because there is no way to specify what row of the middle child to use. For example, you cannot change rows in a table like invoices_lineitems_discounts because there is no way to specify the lineitem that contains the discount you are updating.
• Some environments like SSIS may not be able to operate on child tables at all because they do not have primary keys.

The NewChildJoins data model is fully relational. In this mode non-child tables have the same Document.Id as before, but child tables are extended to have both a foreign key and a primary key. The foreign key is called Document.Parent and it refers to the Document.Id of the row in the parent table that contains the child row. The primary key is called Document.Id and it contains a path which uniquely refers to that child row.

For example, the same tables as above would look like this in the NewChildJoins model. invoices would be the same:

Document.Id	customer
1	Adam
2	Beatrice
3	Charlie

However, invoices_lineitems would have both a primary and foreign key. The primary key contains the ID of the parent row as well as the child row's position in the parent.

Document.Id	Document.Parent	item
1$1	1	laptop
1$2	1	keyboard
2$1	2	stapler
3$1	3	whiteboard
3$2	3	markers

This fixes the limitations of the old data model:

• Complex JOIN results are always consistent because they link foreign keys to primary keys. SELECT * FROM invoices INNERT JOIN invoices_lineitems ON invoices.[Document.Id] = invoices_lineitems.[Document.Parent]
• DML operations on nested child tables are allowed because the Document.Id contains all the required information to pick out specific rows, regardless of the table's depth.
• Environments which depend on primary keys can use these tables and generate JOIN queries since the relationships between Document.Id and Document.Parent columns are included in the Sync App metadata.

This section provides a complete list of the Miscellaneous properties you can configure in the connection string for this provider.

---

Property	Description
AllowJSONParameters	Allows raw JSON to be used in parameters when QueryPassthrough is enabled.
ChildSeparator	The character or characters used to denote child tables.
CreateTableRamQuota	The default RAM quota, in megabytes, to use when inserting buckets via the CREATE TABLE syntax.
DataverseSeparator	The character or characters used to denote Analytics dataverses and scopes/collections.
FlattenArrays	The number of elements to expose as columns from nested arrays. Ignored if IgnoreChildAggregates is enabled.
FlattenObjects	Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON.
FlavorSeparator	The character or characters used to denote flavors.
GenerateSchemaFiles	Indicates the user preference as to when schemas should be generated and saved.
InsertNullValues	Determines whether an INSERT should include fields that have NULL values.
MaxRows	Limits the number of rows returned rows when no aggregation or group by is used in the query. This helps avoid performance issues at design time.
Other	These hidden properties are used only in specific use cases.
Pagesize	The maximum number of results to return per page from Couchbase.
PeriodsSeparator	The character or characters used to denote hierarchy.
PseudoColumns	This property indicates whether or not to include pseudo columns as columns to the table.
QueryExecutionTimeout	This sets the server-side timeout for the query, which governs how long Couchbase will execute the query before returning a timeout error.
QueryPassthrough	This option passes the query to the Couchbase server as is.
RowScanDepth	The maximum number of rows to scan to look for the columns available in a table.
StrictComparison	Adjusts how precisely to translate filters on SQL input queries into Couchbase queries. This can be set to a comma-separated list of values, where each value can be one of: date, number, boolean, or string.
Timeout	The value in seconds until the timeout error is thrown, canceling the operation.
TransactionDurability	Specifies how a document must be stored for a transaction to succeed. Specifies whether to use N1QL transactions when executing queries.
TransactionTimeout	This sets the amount of time a transaction may execute before it is timed out by Couchbase.
UpdateNullValues	Determines whether an UPDATE writes NULL values as NULL, or removes them.
UseCollectionsForDDL	Whether to assume that CREATE TABLE statements use collections instead of flavors. Only takes effect when connecting to Couchbase v7+ and GenerateSchemaFiles is set to OnCreate.
UserDefinedViews	A filepath pointing to the JSON configuration file containing your custom views.
UseTransactions	Specifies whether to use N1QL transactions when executing queries.
ValidateJSONParameters	Allows the provider to validate that string parameters are valid JSON before sending the query to Couchbase.

Allows raw JSON to be used in parameters when QueryPassthrough is enabled.

Remarks

This option affects how string parameters are handled when using direct N1QL and SQL++ queries through QueryPassthrough. For example, consider this query:

INSERT INTO `bucket` (KEY, VALUE) VALUES ("1", @x)

By default, this option is disabled and string parameters are quoted and escaped into JSON strings. That means that any value can be safely used as a string parameter, but it also means that parameters cannot be used as raw JSON documents:

/*
 * If @x is set to: test value " contains quote
 *
 * Result is a valid query
*/
INSERT INTO `bucket` (KEY, VALUE) VALUES ("1", "test value \" contains quote")

/*
 * If @x is set to: {"a": ["valid", "JSON", "value"]}
 *
 * Result contains string instead of JSON document
*/
INSERT INTO `bucket` (KEY, VALUE) VALUES ("1", "{\"a\": [\"valid\", \"JSON\", \"value\"]})

When this option is enabled, string parameters are assumed to be valid JSON. This means that raw JSON documents can be used as parameters, but it also means that all simple strings must be escaped:

/*
 * If @x is set to: test value " contains quote
 *
 * Result is an invalid query
*/
INSERT INTO `bucket` (KEY, VALUE) VALUES ("1", test value " contains quote)

/*
 * If @x is set to: {"a": ["valid", "JSON", "value"]}
 *
 * Result is a JSON document
*/
INSERT INTO `bucket` (KEY, VALUE) VALUES ("1", {"a": ["valid", "JSON", "value"]})

Please refer to ValidateJSONParameters for more details on how parameters are validated when this option is enabled.

The character or characters used to denote child tables.

Remarks

When creating a child table for an array underneath a bucket, the Sync App will generate the name of the child table by concatenating the name of the base table, along with this separator and each path element.

For example, if this document were in the bucket "customers", then the child table for the addresses field would be called "customers_addresses".

{
  "addresses": [
    {"street": "123 Main St"},
    {"street": "424 Pleasant Ct"},
    {"street": "719 Blue Way"}
  ]
}

The default RAM quota, in megabytes, to use when inserting buckets via the CREATE TABLE syntax.

Remarks

The default RAM quota, in megabytes, to use when inserting buckets via the CREATE TABLE syntax.

The character or characters used to denote Analytics dataverses and scopes/collections.

Remarks

When using the Analytics serivce, the Sync App will scan all datasets from all available dataverses. To avoid potential name conflicts, it will include the dataverse name and the dataset name in the generated table name.

By default this is set to ".", so that if there is a dataset called "users" on the "Default" dataverse, then the table generated will be "Default.users".

This property is also used when generating table names for collections (on both N1QL and Analytics) on Couchbase 7 and later. For example, a bucket called "users" that has two collections called "active" and "inactive" under the "status" scope would be detected as the tables "users.status.active" and "users.status.inactive".

The number of elements to expose as columns from nested arrays. Ignored if IgnoreChildAggregates is enabled.

Remarks

By default, nested arrays are returned as strings of JSON. The FlattenArrays property can be used to flatten the elements of nested arrays into columns of their own. This is only recommended for arrays that are expected to be short.

Set FlattenArrays to the number of elements you want to return from nested arrays. The specified elements are returned as columns. The zero-based index is concatenated to the column name. Other elements are ignored.

For example, you can return an arbitrary number of elements from an array of strings:

["FLOW-MATIC","LISP","COBOL"]

When FlattenArrays is set to 1, the preceding array is flattened into the following table:

Column Name	Column Value
languages.0	FLOW-MATIC

Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON.

Remarks

Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON. The property name is concatenated onto the object name with an underscore to generate the column name.

For example, you can flatten the nested objects below at connection time:

address : {
  "street" : "123 Main St.",
  "city"   : "Nowhere",
  "state"  : "NY",
  "zip"    : "12345"
}

When FlattenObjects is set to true, the preceding object is flattened into the following table:

Column Name	Column Value
address.street	123 Main St.
address.city	Nowhere
address.state	NY
address.zip	12345

The character or characters used to denote flavors.

Remarks

When the Sync App detects a flavored table, using either a DocType or Infer TypeDetectionScheme, it names flavored tables by concatenating the underlying bucket name, this seprator, and the value of the bucket's primary flavor.

For example, if the Sync App detects the flavor "docType = 'beer'" on the "beer-sample" bucket, then it will generate the table "beer-sample.beer" which contains only documents in "beer-sample" which have the "beer" doctype.

Indicates the user preference as to when schemas should be generated and saved.

Remarks

GenerateSchemaFiles enables you to save the table definitions identified by Automatic Schema Discovery. This property outputs schemas to .rsd files in the path specified by Location.

Available settings are the following:

• Never: A schema file will never be generated.
• OnUse: A schema file will be generated the first time a table is referenced, provided the schema file for the table does not already exist.
• OnStart: A schema file will be generated at connection time for any tables that do not currently have a schema file.
• OnCreate: A schema file will be generated by when running a CREATE TABLE SQL query.

Note that if you want to regenerate a file, you will first need to delete it.

Generate Schemas with SQL

When you set GenerateSchemaFiles to OnUse, the Sync App generates schemas as you execute SELECT queries. Schemas are generated for each table referenced in the query.

When you set GenerateSchemaFiles to OnCreate, schemas are only generated when a CREATE TABLE query is executed.

Generate Schemas on Connection

Another way to use this property is to obtain schemas for every table in your database when you connect. To do so, set GenerateSchemaFiles to OnStart and connect.

Alternatives to Static Schemas

If your data structures are volatile, consider setting GenerateSchemaFiles to Never and using dynamic schemas. See Automatic Schema Discovery for more information about dynamic schemas.

Editing Schemas

Schema files have a simple format that makes them easy to modify. See Custom Schema Definitions for more information.

Determines whether an INSERT should include fields that have NULL values.

Remarks

By default the Sync App uses NULL values provided in an INSERT statement and inserts them as JSON null values.

If this option is disabled, SQL NULL values are ignored during an INSERT. In the case of array columns (FlattenArrays must be set to retrieve these), this means that array indices are shifted over to compensate for the values that have been removed.

Limits the number of rows returned rows when no aggregation or group by is used in the query. This helps avoid performance issues at design time.

Remarks

Limits the number of rows returned rows when no aggregation or group by is used in the query. This helps avoid performance issues at design time.

These hidden properties are used only in specific use cases.

Remarks

The properties listed below are available for specific use cases. Normal driver use cases and functionality should not require these properties.

Specify multiple properties in a semicolon-separated list.

Integration and Formatting

DefaultColumnSize	Sets the default length of string fields when the data source does not provide column length in the metadata. The default value is 2000.
ConvertDateTimeToGMT	Determines whether to convert date-time values to GMT, instead of the local time of the machine.
RecordToFile=filename	Records the underlying socket data transfer to the specified file.

The maximum number of results to return per page from Couchbase.

Remarks

The Pagesize property affects the maximum number of results to return per page from Couchbase. Setting a higher value may result in better performance at the cost of additional memory allocated per page consumed.

The character or characters used to denote hierarchy.

Remarks

When flattening objects and arrays, the Sync App will use this value to separate different levels of objects and arrays. For example, if your Couchbase server returns a document like this (and FlattenObjects is enabled), then the Sync App will return the columns "geo.latitude" and "geo.longitude" if the periods separator is set to ".".

{
  "geo": {
    "latitude": 35.9132,
    "longitude": -79.0558
  }
}

This property indicates whether or not to include pseudo columns as columns to the table.

Remarks

This setting is particularly helpful in Entity Framework, which does not allow you to set a value for a pseudo column unless it is a table column. The value of this connection setting is of the format "Table1=Column1, Table1=Column2, Table2=Column3". You can use the "*" character to include all tables and all columns; for example, "*=*".

This sets the server-side timeout for the query, which governs how long Couchbase will execute the query before returning a timeout error.

Remarks

Th default is -1, which disables the timeout. When enabling the timeout, the value must include both an amount and a unit, which can be one of: "ns" (nanoseconds), "us" (microseconds), "ms" (milliseconds), "s" (seconds), "m" (minutes) or "h" (hours). For example, "5m" and "300s" both set timeouts of 5 minutes.

There is a server-side timeout as well called the "index scan timeout", which will override this one if it is lower. By default the index scan timeout is 2 minutes, but it can be changed by setting the "indexer.settings.scan_timeout" property on your Couchbase server.

This option passes the query to the Couchbase server as is.

Remarks

When this is set, queries are passed through directly to Couchbase.

The maximum number of rows to scan to look for the columns available in a table.

Remarks

The columns in a table must be determined by scanning table rows. This value determines the maximum number of rows that will be scanned.

Setting a high value may decrease performance. Setting a low value may prevent the data type from being determined properly, especially when there is null data.

Adjusts how precisely to translate filters on SQL input queries into Couchbase queries. This can be set to a comma-separated list of values, where each value can be one of: date, number, boolean, or string.

Remarks

This option is empty by default, which means that WHERE clauses sent to Couchbase will include extra functions that convert values so that more comparisons work.

For example, leaving the "string" setting out of the list causes arrays to be converted, so that they can be compared with strings:

SELECT * FROM Bucket WHERE MyArrayColumn = '[1,2,3]'

If set to a value, queries including the relevant types of comparisons will be translated literally. This makes better use of Couchbase's indexes, but means that the types of comparisons must be in a format Couchbase can compare directly.

For example, if "date" is provided as one of the options, then dates must match the format they are stored as in Couchbase since they will not be converted automatically:

SELECT * FROM Bucket WHERE MyDateColumn = '2018-10-31T10:00:00';

The value in seconds until the timeout error is thrown, canceling the operation.

Remarks

If Timeout = 0, operations do not time out. The operations run until they complete successfully or until they encounter an error condition.

If Timeout expires and the operation is not yet complete, the Sync App throws an exception.

Specifies how a document must be stored for a transaction to succeed. Specifies whether to use N1QL transactions when executing queries.

Remarks

If UseTransactions is enabled, then this option can be set to determine when Couchbase will allow writes in transactions to commit. The Couchbase documentation on Durability and Transactions contains the full details, below is a high-level summary.

This option controls requirements on both quorum and persistence. The quorum may either require no bucket replicas to receive the document (None), or a majority of replicas to have the document (all others). The persistence level requires either that the document be stored in the replica memory (Majoriy) or on the replica disk (MajorityAndPersistActive, PersistToMajority).

None is only useful if the bucket you are using is not configured for replicas. The other options can be used depending on the required performance and durability tradeoffs. Persisting to more replicas is slower but provides greater resilience against a node crashing.

This sets the amount of time a transaction may execute before it is timed out by Couchbase.

Remarks

If transactions are enabled, then the Sync App will default to the server's default transaction timeout setting.

When enabling the timeout, the value must include both an amount and a unit, which can be one of: "ns" (nanoseconds), "us" (microseconds), "ms" (milliseconds), "s" (seconds), "m" (minutes) or "h" (hours). For example, "5m" and "300s" both set timeouts of 5 minutes.

There are also cluster-level and node-level transaction timeouts which override this one if they are smaller. For example, if the node-level timeout is set to a minute then setting this option to "5m" will have no effect.

Determines whether an UPDATE writes NULL values as NULL, or removes them.

Remarks

By default the Sync App will use NULL values provided in an UPDATE statement and set the field in Couchbase to NULL.

If this option is disabled SQL NULL values in an UPDATE will cause the Sync App to mark the field as MISSING. This removes the field from the object containing it, or if the field is contained in an array (per FlattenArrays) then that element is set to NULL.

This option should be used with care as the Sync App may not detect that the field exists if it is removed from enough documents within a bucket.

Whether to assume that CREATE TABLE statements use collections instead of flavors. Only takes effect when connecting to Couchbase v7+ and GenerateSchemaFiles is set to OnCreate.

Remarks

Normally the Sync App will assume that compound table names referenced in a CREATE TABLE statement are flavors. For compatibility, this is still the default with Couchbase v7+ even though flavors are not recommended there.

CREATE TABLE [myBucket.myFlavor](
  [Document.Id] VARCHAR PRIMARY KEY,
  docType VARCHAR,
  sometext VARCHAR,
  somenum INT
)

Enable this option to assume that CREATE TABLE statements refer to collection instead. In that scenario this query willl create the bucket and scope if necessary, before creating the colleciton and setting a primary index:

CREATE TABLE [myBucket.myScope.myCollection](
  [Document.Id] VARCHAR PRIMARY KEY,
  sometext VARCHAR,
  somenum INT
)

A filepath pointing to the JSON configuration file containing your custom views.

Remarks

User Defined Views are defined in a JSON-formatted configuration file called UserDefinedViews.json. The Sync App automatically detects the views specified in this file.

You can also have multiple view definitions and control them using the UserDefinedViews connection property. When you use this property, only the specified views are seen by the Sync App.

This User Defined View configuration file is formatted as follows:

• Each root element defines the name of a view.
• Each root element contains a child element, called query, which contains the custom SQL query for the view.

For example:

{
	"MyView": {
		"query": "SELECT * FROM Customer WHERE MyColumn = 'value'"
	},
	"MyView2": {
		"query": "SELECT * FROM MyTable WHERE Id IN (1,2,3)"
	}
}

Use the UserDefinedViews connection property to specify the location of your JSON configuration file. For example:

"UserDefinedViews", "C:\\Users\\yourusername\\Desktop\\tmp\\UserDefinedViews.json"

Specifies whether to use N1QL transactions when executing queries.

Remarks

By default the Sync App does not use transactions for compatibility with older versions of Couchbase. All of the other options require a connection to Couchbase 7 or above. The N1QL service must also be enabled using CouchbaseService.

Setting this to Always means that all queries will use transactions. An explicit transaction may be created on the connection and queries will use that transaction while it is active. If there is no explicit transaction then queries will use implicit transactions instead.

Setting this to Explicit enables support for explicit transactions only. Explicit transactions may be created but if one is not currently active, then statements will not create an implicit transaction.

Allows the provider to validate that string parameters are valid JSON before sending the query to Couchbase.

Remarks

When AllowJSONParameters and QueryPassthrough are enabled, the query parameters given to the Sync App will be treated as raw JSON documents instead of arbitrary string values. This option controls what happens when invalid JSON is given to the Sync App in this mode.

When this option is enabled, the Sync App will check that all string parameters can be parsed as valid JSON. If any cannot be, an error will be raised and the query will not be run.

When this option is disabled, no check is performed and all string parameter values are substituted into the query directly. This makes executing prepared statements faster, but less safe since invalid N1QL or SQL++ may be sent to the Couchbase.