This page provides a guide to Establishing a Connection to Azure Cosmos DB in CData Cloud, as well as information on the available resources, and a reference to the available connection properties.

Connecting to Azure Cosmos DB

Establishing a Connection shows how to authenticate to Azure Cosmos DB and configure any necessary connection properties to create a database in CData Cloud

Accessing Data from CData Cloud Services

Accessing data from Azure Cosmos DB through the available standard services and CData Cloud administration is documented in further details in the CData Cloud Documentation.

Connect to Azure Cosmos DB by selecting the corresponding icon in the Database tab. Required properties are listed under Settings. The Advanced tab lists connection properties that are not typically required.

Before You Connect

Role Assignment

Configure role-based access control for your Azure Cosmos DB account with Azure AD

You can either assign one of the built-in role definitions:

• CosmosDB Built-in Data Reader
• CosmosDB Built-in Data Contributor

or create your own custom role definitions. You must also set the scope of the role assignment, where "/" means that the identity has access to all the databases.

Connecting to Azure Cosmos DB

Account Key

Log in to the Azure Portal, select Azure Cosmos DB, and select your account.

Set the following to authenticate:

• AccountEndpoint: The Cosmos DB account URL. Set this to the URI value found in the Settings > Keys blade of the Cosmos DB account.
• AccountKey: A master key token or a resource token for connecting to Azure Cosmos DB. Set this to the PRIMARY KEY value found in the Settings > Keys blade of the Cosmos DB account.
• TokenType: (optional). Set this to "master" (the default value) if you are using a Master Token, which is a full permissions token generated during account creation. Otherwise, set this property to "resource" if you are using a Resource Token, which is a custom permissions token generated when a database user is set up.

Azure AD

Azure Service Principal

Azure Service Principal is role-based application-based authentication. This means that authentication is done per application, rather than per user. All tasks taken on by the application are executed without a default user context, but based on the assigned roles. The application access to the resources is controlled through the assigned roles' permissions.

For information about how to set up Azure Service Principal authentication, see Creating a Custom OAuth Application.

Azure Service Principal

Azure Service Principal is role-based application-based authentication. This means that authentication is done per application, rather than per user. All tasks taken by the app are done without a default user context, but based on the assigned roles. The application access to the resources is controlled through the assigned roles' permissions.

To use Azure Service Principal authentication, you must:

• Set up the ability to assign a role to the authentication application. To do this, create a custom OAuth AD application, as described in Creating a Custom OAuth Application.
• Register an application with an Azure AD tenant, to create a new service principal that can be used with the role-based access control, to access resources in your subscription.

Do the following:

1. Create a custom Azure AD application, as described in Creating a Custom OAuth Application.
2. Assign a role to the application:
   1. Use the search bar to search for the Subscriptions service.
   2. Open the Subscriptions page.
   3. Select the subscription to which to assign the application.
   4. Open the Access control (IAM).
   5. Select Add > Add role assignment. Azure Cosmos DB opens the Add role assignment page.
   6. Assign your custom Azure AD application the role of Owner.

Client Credentials

All permissions related to the client OAuth flow require admin consent. This means you cannot use the application embedded with the CData Cloud in the client OAuth flow. You must create your own OAuth application to use client credentials. See Creating a Custom OAuth Application for more information.

In your App Registration in portal.azure.com, navigate to API Permissions and select the Microsoft Graph permissions. There are two distinct sets of permissions: Delegated permissions and Application permissions. The permissions used during client credential authentication are under "Application Permissions".

Select the permissions you require for your integration. After you do this, set the following connection properties:

• AuthScheme: AzureServicePrincipal.
• InitiateOAuth: GETANDREFRESH. You can use InitiateOAuth to avoid repeating the OAuth exchange and manually setting the OAuthAccessToken.
• AzureTenant: The tenant you wish to connect to.
• OAuthGrantType: CLIENT.
• OAuthClientId: The client Id in your application settings.
• OAuthClientSecret: The client secret in your application settings.

Authentication with client credentials takes place automatically like any other connection, except there is no window opened prompting the user. Because there is no user context, there is no need for a browser popup. Connections will take place and be handled internally.

Fine Tuning Data Access

You can use the following properties to gain greater control over Azure Cosmos DB API features and the strategies the Cloud uses to surface them:

• RowScanDepth: This property determines the number of rows that will be scanned to detect column data types when generating table metadata.
• TypeDetectionScheme: This property allows more control over the strategy implemented by the RowScanDepth property.

• GenerateSchemaFiles: This property enables you to persist table metadata in static schema files that are easy to customize, to persist your changes to column data types, for example.
  You can set this property to "OnStart" to generate schema files for all tables in your database at connection. Or, you can generate schemas as you execute SELECT queries to tables.
  The resulting schemas are based on the connection properties you use to configure Automatic Schema Discovery
  To use the resulting schema files, set the Location property to the folder containing the schemas.

Just as described in the SQL Compliance the Cloud supports batch CUD (Create, Update, Delete) operations. Batch processing is achieved by issuing multiple requests simultaneously. Even though this method greatly improves the performance for write operations, the cost of these operations is relatively high, thus the Request Units (RU) budget per second for a certain container or database may be exceeded. Depending on your Azure Cosmos DB Service Quotas, exceeding the RU budgets may incur in extra costs, or it may even temporary throttle or interrupt the Azure Cosmos DB usage for other workloads.

In order to avoid exceeding the RU budget per second, the Cloud dynamically adjusts the number of concurrent requests per second depending on the set WriteThroughputBudget and the constantly adjusted average RU cost per statement. The user can utilize the WriteThroughputBudget connection property to define the RU budged per second, that batch write operations should not exceed. Another important factor in batch write operations is the MaxThreads connection property, which specifies the maximum number of concurrent requests. If using a low MaxThreads value, the Cloud might not be able to efficiently use the available budget.

Since the requests throttling logic is applied client-side, in a few cases the RU/s budged may be exceeded by a relatively small amount. These cases include inserting, updating and deleting records with highly variable column count and input value length per column.

Note: By default, the WriteThroughputBudget property is set 1000 RU/s and the MaxThreads property is set to 200 threads.

Azure Cosmos DB is a schemaless, document database that provides high performance, availability, and scalability. These features are not necessarily incompatible with a standards-compliant query language like SQL-92. In this section we will show various schemes that the Cloud offers to bridge the gap with relational SQL and a document database.

Working with Azure Cosmos DB Objects as Tables

The Cloud models the schemaless Azure Cosmos DB objects into relational tables and translates SQL queries into Azure Cosmos DB queries to get the requested data. See Query Mapping (Sql API) for more details on how various Azure Cosmos DB operations are represented as SQL.

Discovering Schemas Automatically

The Automatic Schema Discovery scheme automatically finds the data types in a Azure Cosmos DB object by scanning a configured number of rows of the object. You can use RowScanDepth, FlattenArrays, and FlattenObjects to control the relational representation of the collections in Azure Cosmos DB. You can also write Free-Form Queries not tied to the schema.

Customizing Schemas

Optionally, you can use Custom Schema Definitions to project your chosen relational structure on top of a Azure Cosmos DB object. This allows you to define your chosen names of columns, their data types, and the location of their values in the collection.

Set GenerateSchemaFiles to save the detected schemas as simple configuration files that are easy to extend. You can persist schemas for all collections in the database or for the results of SELECT queries.

Limitations of the RawValue TypeDetectionScheme

If the TypeDetectionScheme is set to RawValue, the Cloud will push each document as single aggregate value on a column named JsonData, along with its resource identifier on the separate Primary Key column. The JSON documents are not processed, and as a result, the below functionalities are NOT supported with this configuration.

• Automatic Schema Discovery
• Free-Form Queries
• Vertical Flattening
• SQL API Built-In Functions
• SQL API GROUP BY
• Almost all server side supported filters apart from WHERE clause conditions built with the resource identifier.

The Cloud automatically infers a relational schema by inspecting a series of Azure Cosmos DB documents in a collection. You can use the RowScanDepth property to define the number of documents the Cloud will scan to do so. The columns identified during the discovery process depend on the FlattenArrays and FlattenObjects properties.

Flattening Objects

If FlattenObjects is set, all nested objects will be flattened into a series of columns. For example, consider the following document:

{
  id: 12,
  name: "Lohia Manufacturers Inc.",
  address: {street: "Main Street", city: "Chapel Hill", state: "NC"},
  offices: ["Chapel Hill", "London", "New York"],
  annual_revenue: 35,600,000
}

If FlattenObjects is not set, then the address.street, address.city, and address.state columns will not be broken apart. The address column of type string will instead represent the entire object. Its value would be {street: "Main Street", city: "Chapel Hill", state: "NC"}. See JSON Functions for more details on working with JSON aggregates.

You can change the separator character in the column name from a dot by setting SeparatorCharacter.

Flattening Arrays

The FlattenArrays property can be used to flatten array values into columns of their own. This is only recommended for arrays that are expected to be short, for example the coordinates below:

"coord": [ -73.856077, 40.848447 ]

It is best to leave other unbounded arrays as they are and piece out the data for them as needed using JSON Functions.

As discussed in Automatic Schema Discovery, intuited table schemas enable SQL access to unstructured Azure Cosmos DB data. JSON Functions enable you to use standard JSON functions to summarize Azure Cosmos DB data and extract values from any nested structures. Custom Schema Definitions enable you to define static tables and give you more granular control over the relational view of your data; for example, you can write schemas defining parent/child tables or fact/dimension tables. However, you are not limited to these schemes.

After connecting you can query any nested structure without flattening the data. Any relations that you can access with FlattenArrays and FlattenObjects can also be accessed with an ad hoc SQL query.

Let's consider an example document from the following Restaurant data set:

 
{
  "address": {
    "building": "1007",
    "coord": [
      -73.856077,
      40.848447
    ],
    "street": "Morris Park Ave",
    "zipcode": "10462"
  },
  "borough": "Bronx",
  "cuisine": "Bakery",
  "grades": [
    {
      "grade": "A",
      "score": 2,
      "date": {
        "$date": "1393804800000"
      }
    },
    {
      "date": {
        "$date": "1378857600000"
      },
      "grade": "B",
      "score": 6
    },
    {
      "score": 10,
      "date": {
        "$date": "1358985600000"
      },
      "grade": "C"
    }
  ],
  "name": "Morris Park Bake Shop",
  "restaurant_id": "30075445"
} 

SELECT [address.building], [grades.1.grade] FROM restaurants WHERE restaurant_id = '30075445'

It is possible to retrieve an array of documents as if it were a separate table. Take the following JSON structure from the restaurants collection for example:

{
  "_id" : ObjectId("568c37b748ddf53c5ed98932"),
  "address" : {
    "building" : "1007",
    "coord" : [-73.856077, 40.848447],
    "street" : "Morris Park Ave",
    "zipcode" : "10462"
  },
  "borough" : "Bronx",
  "cuisine" : "Bakery",
  "grades" : [{
      "date" : ISODate("2014-03-03T00:00:00Z"),
      "grade" : "A",
      "score" : 2
    }, {
      "date" : ISODate("2013-09-11T00:00:00Z"),
      "grade" : "A",
      "score" : 6
    }, {
      "date" : ISODate("2013-01-24T00:00:00Z"),
      "grade" : "A",
      "score" : 10
    }, {
      "date" : ISODate("2011-11-23T00:00:00Z"),
      "grade" : "A",
      "score" : 9
    }, {
      "date" : ISODate("2011-03-10T00:00:00Z"),
      "grade" : "B",
      "score" : 14
    }],
  "name" : "Morris Park Bake Shop",
  "restaurant_id" : "30075445"
}

SELECT * FROM [restaurants.grades]

You may also want to include information from the base restaurants table. You can do this with a join. Flattened arrays can only be joined with the root document. The Cloud expects the left part of the join is the array document you want to flatten vertically. Disable SupportEnhancedSQL to join nested Azure Cosmos DB documents -- this type of query is supported through the Azure Cosmos DB API.

SELECT [restaurants].[restaurant_id], [restaurants.grades].* FROM [restaurants.grades] JOIN [restaurants] WHERE [restaurants].name = 'Morris Park Bake Shop'

The Cloud can return JSON structures as column values. The Cloud 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

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

JSON_COUNT

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

JSON_SUM

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

JSON_MIN

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

JSON_MAX

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

DOCUMENT

The DOCUMENT function can be used to retrieve the entire document as a JSON string. See the following query and its result as an example:

SELECT DOCUMENT(*) FROM Customers;

{ "id": 12, "name": "Lohia Manufacturers Inc.", "address": { "street": "Main Street", "city": "Chapel Hill", "state": "NC"}, "offices": [ "Chapel Hill", "London", "New York" ], "annual_revenue": 35,600,000 }

Cosmos DB also supports a number of built-in functions for common operations, that can be used inside queries. Here are some example of how can be used as part of select columns or the WHERE clause:

Use Built-in functions as part of SELECT columns

SELECT IS_NUMBER(user_id) AS ISN_ATTR, IS_NUMBER(id) AS ISN_ID FROM [users]
SELECT POWER(user_id, 2) AS POWERSSS, LENGTH(id) AS LENGTH_ID, PI() AS JustThePI FROM [users]

Use Built-in functions as part of WHERE clause

SELECT * FROM [users] WHERE STARTSWITH(middle_name, 'G')
SELECT * FROM [users] WHERE REPLACE(middle_name, 'Chr', '___') = '___istopher'

Mathematical functions

The mathematical functions each perform a calculation, based on input values that are provided as arguments, and return a numeric value. Here's a table of supported built-in mathematical functions.

Type checking functions

The type checking functions allow you to check the type of an expression within SQL queries. Type checking functions can be used to determine the type of properties within documents dynamically when it is variable or unknown. Here's a table of supported built-in type checking functions.

String functions

The following scalar functions perform an operation on a string input value and return a string, numeric or Boolean value. Here's a table of built-in string functions:

Array functions

The following scalar functions perform an operation on an array input value and return numeric, Boolean or array value. Here's a table of built-in array functions:

Nested functions

You can also perform nested built-in functions, wich will be processed server side as well:

i.e. SELECT TOP 10 CONCAT(SUBSTRING(UPPER(cuisine), 0, 3), '-cuisine') FROM [restaurants]

The GROUP BY clause divides the query's results according to the values of one or more specified properties. This operation is partially done server-side because of some API limitations. We still need to operate a client-side grouping.

GROUP BY Examples

SELECT COUNT(*) AS CNT, gender FROM [users] GROUP BY gender
SELECT COUNT(*) AS CNT, gender, doc_type FROM [users] GROUP BY gender, doc_type

The Cloud maps SQL queries into the corresponding Azure Cosmos DB SQL API queries. A detailed description of all the transformations is out of scope, but we will describe some of the common elements that are used. The Cloud takes advantage of SQL API features such as the aggregation framework to compute the desired results.

SELECT Queries

SELECT id, name FROM Users

SELECT C.id, C.name FROM C

SELECT * FROM Users WHERE name = 'A'

SELECT * FROM C WHERE C.name = 'A'

SELECT * FROM Users WHERE name = 'A' OR email = '[email protected]'

SELECT * FROM C WHERE C.name = 'A' OR C.email = '[email protected]'

SELECT id, grantamt FROM WorldBank WHERE grantamt IN (4500000, 85400000) OR grantamt = 16200000

SELECT C.id, C.grantamt FROM C WHERE C.grantamt IN (4500000, 85400000) OR C.grantamt = 16200000

SELECT * FROM WorldBank WHERE CountryCode = 'A' ORDER BY TotalCommAmt ASC

SELECT * FROM C WHERE C.countrycode = 'AL' ORDER BY C.totalcommamt ASC

SELECT * FROM WorldBank WHERE CountryCode = 'A' ORDER BY TotalCommAmt DESC

SELECT * FROM C WHERE C.countrycode = 'AL' ORDER BY C.totalcommamt DESC

Aggregate Queries

SELECT COUNT(grantamt) AS COUNT_GRAMT FROM WorldBank

SELECT COUNT(C.grantamt) AS COUNT_GRAMT FROM C

SELECT SUM(grantamt) AS SUM_GRAMT FROM WorldBank

SELECT SUM(C.grantamt) AS SUM_GRAMT FROM C

Built-In functions

SELECT IS_NUMBER(grantamt) AS ISN_ATTR, IS_NUMBER(id) AS ISN_ID FROM WorldBank

SELECT IS_NUMBER(C.grantamt) AS ISN_ATTR, IS_NUMBER(C.id) AS ISN_ID FROM C

SELECT POWER(totalamt, 2) AS POWERS_A, LENGTH(id) AS LENGTH_ID, PI() AS ThePI FROM WorldBank

SELECT POWER(C.totalamt, 2) AS POWERS_A, LENGTH(C.id) AS LENGTH_ID, PI() AS ThePI FROM C

You can extend the table schemas created with Automatic Schema Discovery by saving them into schema files. The schema files have a simple format that makes the schemas to edit.

Generating Schema Files

Set GenerateSchemaFiles to "OnStart" to persist schemas for all tables when you connect. You can also generate table schemas as needed: Set GenerateSchemaFiles to "OnUse" and execute a SELECT query to the table.

For example, consider a schema for the restaurants data set. This is a sample data set provided by Azure Cosmos DB.

Below is an example document from the collection:

{
  "address":{
    "building":"461",
      "coord":[
        -74.138492,
        40.631136
      ],
      "street":"Port Richmond Ave",
      "zipcode":"10302"
   },
   "borough":"Staten Island",
   "cuisine":"Other",
   "name":"Indian Oven",
   "restaurant_id":"50018994"
}

Customizing a Schema

When GenerateSchemaFiles is set, the Cloud saves schemas into the folder specified by the Location property. You can then change column behavior in the resulting schema.

The following schema uses the other:bsonpath property to define where in the collection to retrieve the data for a particular column. Using this model you can flatten arbitrary levels of hierarchy.

Below are the corresponding column definitions for the restaurants data set. In Custom Schema Example, you will find the complete schema.

<rsb:script xmlns:rsb="http://www.rssbus.com/ns/rsbscript/2">  

  <rsb:info title="StaticRestaurants" description="Custom Schema for the restaurants data set.">  
    <!-- Column definitions -->
    <attr   name="_rid"               xs:type="string"   key="true"   other:collrid="hWdRAKRi3Pg=" other:dbrid="hWdRAA==" other:partitionpath="/name" />
	<attr   name="borough"            xs:type="string"   />
    <attr   name="cuisine"            xs:type="string"   />
    <attr   name="address.building"   xs:type="string"   />
    <attr   name="address.street"     xs:type="string"   />
    <attr   name="address.coord.0"    xs:type="double"   />
    <attr   name="address.coord.1"    xs:type="double"   />
    <input name="rows@next" desc="Internal attribute used for paging through data."  />
  </rsb:info>  

  <rsb:set attr="collection" value="restaurants"/>

</rsb:script>

This section contains a complete schema. The info section enables a relational view of a Azure Cosmos DB 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.

Copy the rows@next input as-is into your schema. The operations, such as cosmosdbadoSysData, are internal implementations and can also be copied as is.

Set the Location property to the file directory that will contain the schema file.

When, creating custom schemas, the attr for _rid, shown below, is required.

Also required are three properties for the _rid column definition:

• other:dbrid is found in the _self property of an item in the collection, after "dbs/".
• other:collrid is found in the _self property of an item in the collection, after "/colls/".
• other:partitionpath refers to the name of the partition specified when the collection was created.

<rsb:script xmlns:rsb="http://www.rssbus.com/ns/rsbscript/2">  

  <rsb:info title="StaticRestaurants" description="Custom Schema for the restaurants data set.">  
    <!-- Column definitions -->
	<attr   name="_rid"               xs:type="string"   key="true"   other:collrid="hWdRAKRi3Pg=" other:dbrid="hWdRAA==" other:partitionpath="/name" />
    <attr   name="borough"            xs:type="string"   />
    <attr   name="cuisine"            xs:type="string"   />
    <attr   name="address.building"   xs:type="string"   />
    <attr   name="address.street"     xs:type="string"   />
    <attr   name="address.coord.0"    xs:type="double"   />
    <attr   name="address.coord.1"    xs:type="double"   />
    <input name="rows@next" desc="Internal attribute used for paging through data."  />
  </rsb:info>  

  <rsb:script method="GET">
    <rsb:call op="cosmosdbadoSysData">
      <rsb:push />
    </rsb:call>
  </rsb:script>

  <rsb:script method="POST">
    <rsb:call op="cosmosdbadoSysData">
      <rsb:push />
    </rsb:call>
  </rsb:script>

  <rsb:script method="MERGE">
    <rsb:call op="cosmosdbadoSysData">
      <rsb:push />
    </rsb:call>
  </rsb:script>

  <rsb:script method="DELETE">
    <rsb:call op="cosmosdbadoSysData">
      <rsb:push />
    </rsb:call>
  </rsb:script>

</rsb:script>

You can query the system tables described in this section to access schema information, information on data source functionality, and batch operation statistics.

Schema Tables

The following tables return database metadata for Azure Cosmos DB:

• sys_catalogs: Lists the available databases.
• sys_schemas: Lists the available schemas.
• sys_tables: Lists the available tables and views.
• sys_tablecolumns: Describes the columns of the available tables and views.
• sys_procedures: Describes the available stored procedures.
• sys_procedureparameters: Describes stored procedure parameters.
• sys_keycolumns: Describes the primary and foreign keys.
• sys_indexes: Describes the available indexes.

Data Source Tables

The following tables return information about how to connect to and query the data source:

• sys_connection_props: Returns information on the available connection properties.
• sys_sqlinfo: Describes the SELECT queries that the Cloud can offload to the data source.

Query Information Tables

The following table returns query statistics for data modification queries, including batch operations::

• sys_identity: Returns information about batch operations or single updates.

Lists the available databases.

The following query retrieves all databases determined by the connection string:

SELECT * FROM sys_catalogs

Columns

Lists the available schemas.

The following query retrieves all available schemas:

          SELECT * FROM sys_schemas
          

Columns

Lists the available tables.

The following query retrieves the available tables and views:

          SELECT * FROM sys_tables
          

Columns

Describes the columns of the available tables and views.

The following query returns the columns and data types for the [CData].[Entities].Customers table:

SELECT ColumnName, DataTypeName FROM sys_tablecolumns WHERE TableName='Customers' AND CatalogName='CData' AND SchemaName='Entities'

Columns

Lists the available stored procedures.

The following query retrieves the available stored procedures:

          SELECT * FROM sys_procedures
          

Columns

Describes stored procedure parameters.

The following query returns information about all of the input parameters for the EVAL stored procedure:

SELECT * FROM sys_procedureparameters WHERE ProcedureName='EVAL' AND Direction=1 OR Direction=2

Columns

Describes the primary and foreign keys.

The following query retrieves the primary key for the [CData].[Entities].Customers table:

         SELECT * FROM sys_keycolumns WHERE IsKey='True' AND TableName='Customers' AND CatalogName='CData' AND SchemaName='Entities'
          

Columns

Describes the foreign keys.

The following query retrieves all foreign keys which refer to other tables:

         SELECT * FROM sys_foreignkeys WHERE ForeignKeyType = 'FOREIGNKEY_TYPE_IMPORT'
          

Columns

Describes the primary keys.

The following query retrieves the primary keys from all tables and views:

         SELECT * FROM sys_primarykeys
          

Columns

Describes the available indexes. By filtering on indexes, you can write more selective queries with faster query response times.

The following query retrieves all indexes that are not primary keys:

          SELECT * FROM sys_indexes WHERE IsPrimary='false'
          

Columns

Returns information on the available connection properties and those set in the connection string.

When querying this table, the config connection string should be used:

jdbc:cdata:cosmosdb:config:

This connection string enables you to query this table without a valid connection.

The following query retrieves all connection properties that have been set in the connection string or set through a default value:

SELECT * FROM sys_connection_props WHERE Value <> ''

Columns

Describes the SELECT query processing that the Cloud can offload to the data source.

See SQL Compliance for SQL syntax details.

Discovering the Data Source's SELECT Capabilities

Below is an example data set of SQL capabilities. Some aspects of SELECT functionality are returned in a comma-separated list if supported; otherwise, the column contains NO.

The following query retrieves the operators that can be used in the WHERE clause:

SELECT * FROM sys_sqlinfo WHERE Name = 'SUPPORTED_OPERATORS'

Columns

Returns information about attempted modifications.

The following query retrieves the Ids of the modified rows in a batch operation:

         SELECT * FROM sys_identity
          

Columns

Stored procedures are function-like interfaces that extend the functionality of the Cloud beyond simple SELECT/INSERT/UPDATE/DELETE operations with Azure Cosmos DB.

Stored procedures accept a list of parameters, perform their intended function, and then return any relevant response data from Azure Cosmos DB, along with an indication of whether the procedure succeeded or failed.

CData Cloud - Azure Cosmos DB Stored Procedures

Insert entire JSON string to CosmosDB.

Input

Result Set Columns

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.

Authentication

Azure Authentication

OAuth

JWT OAuth

SSL

Logging

Schema

Miscellaneous

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

The type of authentication to use when connecting to Azure Cosmos DB.

Possible Values

Data Type

string

Default Value

"AccountKey"

Remarks

• AccountKey: Set this to perform authentication with AccountKey and AccountEndpoint.
• AzureAD: Set this to perform Azure Active Directory OAuth authentication.
• AzureServicePrincipal: Set this to authenticate as an Azure Service Principal using a Client Secret.
• AzureServicePrincipalCert: Set this to authenticate as an Azure Service Principal using a Certificate.

The value should be the Cosmos DB account URL from the Keys blade of the Cosmos DB account.

Data Type

string

Default Value

""

Remarks

The value should be the Cosmos DB account URL from the Keys blade of the Cosmos DB account.

A master key token or a resource token for connecting to the Azure Cosmos DB REST API.

Data Type

string

Default Value

""

Remarks

In the Azure portal, navigate to the Cosmos DB service and select your Azure Cosmos DB account. From the resource menu, go to the Keys page. Find the PRIMARY KEY value and set Token to this value.

Denotes the type of token: master or resource.

Possible Values

Data Type

string

Default Value

"master"

Remarks

The master key is created during the creation of an account. There are two sets of master keys, the primary key and the secondary key. The administrator of the account can then exercise key rotation using the secondary key. In addition, the account administrator can also regenerate the keys as needed.

Resource tokens are created when users in a database are set up with access permissions for precise access control on a resource, also known as a permission resource. A permission resource contains a hash resource token constructed with the information regarding the resource path and access type a user has access to. The permission resource token is time bound and the validity period can be overridden. When a permission resource is acted upon on (POST, GET, PUT), a new resource token is generated.

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

The Microsoft Online tenant being used to access data. If not specified, your default tenant is used.

Data Type

string

Default Value

""

Remarks

The Microsoft Online tenant being used to access data. For instance, contoso.onmicrosoft.com. Alternatively, specify the tenant Id. This value is the directory Id in the Azure Portal > Azure Active Directory > Properties.

Typically it is not necessary to specify the Tenant. This can be automatically determined by Microsoft when using the OAuthGrantType set to CODE (default). However, it may fail in the case that the user belongs to multiple tenants. For instance, if an Admin of domain A invites a user of domain B to be a guest user. The user will now belong to both tenants. It is a good practice to specify the Tenant, although in general things should normally work without having to specify it.

The AzureTenant is required when setting OAuthGrantType to CLIENT. When using client credentials, there is no user context. The credentials are taken from the context of the app itself. While Microsoft still allows client credentials to be obtained without specifying which Tenant, it has a much lower probability of picking the specific tenant you want to work with. For this reason, we require AzureTenant to be explicitly stated for all client credentials connections to ensure you get credentials that are applicable for the domain you intend to connect to.

The Microsoft Online tenant being used to access data. For instance, contoso.onmicrosoft.com. Alternatively, specify the tenant Id. This value is the directory Id in the Azure Portal > Azure Active Directory > Properties.

Typically it is not necessary to specify the Tenant. This can be automatically determined by Microsoft when using the OAuthGrantType set to CODE (default). However, it may fail in the case that the user belongs to multiple tenants. For instance, if an Admin of domain A invites a user of domain B to be a guest user. The user will now belong to both tenants. It is a good practice to specify the Tenant, although in general things should normally work without having to specify it.

The AzureTenant is required when setting OAuthGrantType to CLIENT. When using client credentials, there is no user context. The credentials are taken from the context of the app itself. While Microsoft still allows client credentials to be obtained without specifying which Tenant, it has a much lower probability of picking the specific tenant you want to work with. For this reason, we require AzureTenant to be explicitly stated for all client credentials connections to ensure you get credentials that are applicable for the domain you intend to connect to.

The Azure Environment to use when establishing a connection.

Possible Values

Data Type

string

Default Value

"GLOBAL"

Remarks

In most cases, leaving the environment set to global will work. However, if your Azure Account has been added to a different environment, the AzureEnvironment may be used to specify which environment. The available values are GLOBAL, CHINA, USGOVT, USGOVTDOD.

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

The client Id assigned when you register your application with an OAuth authorization server.

Data Type

string

Default Value

""

Remarks

As part of registering an OAuth application, you will receive the OAuthClientId value, sometimes also called a consumer key, and a client secret, the OAuthClientSecret.

The client secret assigned when you register your application with an OAuth authorization server.

Data Type

string

Default Value

""

Remarks

As part of registering an OAuth application, you will receive the OAuthClientId, also called a consumer key. You will also receive a client secret, also called a consumer secret. Set the client secret in the OAuthClientSecret property.

The grant type for the OAuth flow.

Possible Values

Data Type

string

Default Value

"CODE"

Remarks

The following options are available: CODE,CLIENT,PASSWORD

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

The JWT Certificate store.

Data Type

string

Default Value

""

Remarks

The name of the certificate store for the client certificate.

The OAuthJWTCertType field specifies the type of the certificate store specified by OAuthJWTCert. If the store is password protected, specify the password in OAuthJWTCertPassword.

OAuthJWTCert is used in conjunction with the OAuthJWTCertSubject field in order to specify client certificates. If OAuthJWTCert has a value, and OAuthJWTCertSubject is set, a search for a certificate is initiated. Please refer to the OAuthJWTCertSubject field for details.

Designations of certificate stores are platform-dependent.

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

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 (i.e. PKCS12 certificate store).

The type of key store containing the JWT Certificate.

Data Type

string

Default Value

"PEMKEY_BLOB"

Remarks

This property can take one of the following values:

The password for the OAuth JWT certificate.

Data Type

string

Default Value

""

Remarks

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

The subject of the OAuth JWT certificate.

Data Type

string

Default Value

"*"

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 instance "CN=www.server.com, OU=test, C=US, [email protected]". Common fields and their meanings are displayed below.

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

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

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

Data Type

string

Default Value

""

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:

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.

Possible Values

Data Type

string

Default Value

"USER"

Remarks

This property can take one of the following values:

The password for the TLS/SSL client certificate.

Data Type

string

Default Value

""

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.

Data Type

string

Default Value

"*"

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.

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

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

Data Type

string

Default Value

""

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:

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 Logging properties you can configure in the connection string for this provider.

The verbosity level that determines the amount of detail included in the log file.

Data Type

string

Default Value

"1"

Remarks

The verbosity level determines the amount of detail that the Cloud reports to the Logfile. Verbosity levels from 1 to 5 are supported. These are detailed in the Logging page.

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

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

Data Type

string

Default Value

""

Remarks

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

Specify the Azure Cosmos DB database you want to work with.

Data Type

string

Default Value

""

Remarks

Specify the Azure Cosmos DB database you want to work with.

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

Specifies whether will return the calculated value of the aggregates or grouped by partiton range.

Data Type

bool

Default Value

true

Remarks

Specifies whether will return the calculated value of the aggregates or grouped by partiton range.

Denotes the type of token: master or resource.

Possible Values

Data Type

string

Default Value

"SESSION"

Remarks

The consistency level override for read options against documents and attachments. The valid values are: Strong, Bounded, Session, or Eventual (in order of strongest to weakest). The override must be the same or weaker than the account's configured consistency level.

The consistency level override for read options against documents and attachments. The valid values are: Strong, Bounded, Session, or Eventual (in order of strongest to weakest). The override must be the same or weaker than the account's configured consistency level.

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. Set FlattenArrays to the number of elements you want to return from nested arrays.

Data Type

string

Default Value

"0"

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"]

Setting FlattenArrays to -1 will flatten all the elements of nested arrays.

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

Data Type

bool

Default Value

true

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 a dot to generate the column name.

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

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

Force the use of an index scan to process the query if indexing is disabled or the right index path is not available.

Data Type

bool

Default Value

false

Remarks

Queries against containers where indexing is disabled or paths are excluded may fail. Set this property to true to force the use of indexing on the server so the query is processed successfully. By default, queries that require the use of indexing on containers where IndexingMode=None are handled client-side.

Limits the number of rows returned when no aggregation or GROUP BY is used in the query. This takes precedence over LIMIT clauses.

Data Type

int

Default Value

-1

Remarks

Limits the number of rows returned when no aggregation or GROUP BY is used in the query. This takes precedence over LIMIT clauses.

Specifies the maximum number of concurrent requests for Batch CUD (Create, Update, Delete) operations.

Data Type

int

Default Value

200

Remarks

This property should be used in conjunction with the WriteThroughputBudget connection property. The Cloud may execute less parallel requests than the configured MaxThreads value, since it always aims to not exceed the WriteThroughputBudget limit. The number of concurrent requests will also depend on the running machine's resources.

Note: This property is applicable only when executing batch CUD operations.

Aggregate queries in partitioned collections will require parallel requests for different partition ranges. Set this to the number of parallel request to be issued in the same time.

Data Type

string

Default Value

"5"

Remarks

Aggregate queries in partitioned collections will require parallel requests for different partition ranges. Set this to the number of parallel request to be issued in the same time.

The maximum number of results to return per page from Azure Cosmos DB.

Data Type

int

Default Value

1000

Remarks

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

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

Data Type

string

Default Value

""

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, "*=*".

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

Data Type

int

Default Value

100

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.

The character or characters used to denote hierarchy.

Data Type

string

Default Value

"."

Remarks

In order to flatten out hierarchical structures, the Cloud needs some specifier that states the path to a column through the hierarchy. If this value is "." and a column comes back with the name address.city, this indicates that there is a mapped attribute with a child called city. If your data has columns that already use a single period within the attribute name, set the SeparatorCharacter to a different character or characters.

Whether or not to use the collection's Partition Key field as part of composite Primary Key for the corresponding exposed table.

Data Type

bool

Default Value

true

Remarks

By default, this is set to TRUE, and the collection's Partition Key is used as part of the table's composite Primary Key along with the _rid column. If this is set to FALSE, only the _rid column will serve as the Primary Key for the exposed table.

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

Data Type

int

Default Value

60

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 Cloud throws an exception.

Comma-separated options for how the provider will scan the data to determine the fields and datatypes in each document collection.

Data Type

string

Default Value

"RowScan,Recent"

Remarks

Set this property to false to switch using the id column as primary key instead the default _rid.

Data Type

bool

Default Value

true

Remarks

Since CosmosDB allows you to use both _rid and id fields as unique values for retrieving resource data, you can set this property to false to switch using the id column as primary key instead the default _rid.

Defines the Requests Units (RU) budget per Second that the Batch CUD (Create, Update, Delete) operations should not exceed.

Data Type

int

Default Value

1000

Remarks

The Cloud will dynamically adjust the maximum number of requests per second depending on the configured RU budget. Although the Cloud always aims to not exceed the RU budget, since the requests throttling logic is applied client-side, it may be exceeded by a relatively small amount in a few cases. These cases include inserting, updating and deleting records with highly variable column count and input value length per column.

Note: This property is applicable only when executing batch CUD operations.