ADO.NET Provider for GraphQL

Build 21.0.7940

SELECT Statements

A SELECT statement can consist of the following basic clauses.

  • SELECT
  • INTO
  • FROM
  • JOIN
  • WHERE
  • GROUP BY
  • HAVING
  • UNION
  • ORDER BY
  • LIMIT

SELECT Syntax

The following syntax diagram outlines the syntax supported by the SQL engine of the provider:

SELECT {
  [ TOP <numeric_literal> | DISTINCT ]
  { 
    * 
    | { 
        <expression> [ [ AS ] <column_reference> ] 
        | { <table_name> | <correlation_name> } .* 
      } [ , ... ] 
  }
  [ INTO csv:// [ filename= ] <file_path> [ ;delimiter=tab ] ]
  { 
    FROM <table_reference> [ [ AS ] <identifier> ] 
  } [ , ... ]
  [ [  
      INNER | { { LEFT | RIGHT | FULL } [ OUTER ] } 
    ] JOIN <table_reference> [ ON <search_condition> ] [ [ AS ] <identifier> ] 
  ] [ ... ] 
  [ WHERE <search_condition> ]
  [ GROUP BY <column_reference> [ , ... ]
  [ HAVING <search_condition> ]
  [ UNION [ ALL ] <select_statement> ]
  [ 
    ORDER BY 
    <column_reference> [ ASC | DESC ] [ NULLS FIRST | NULLS LAST ]
  ]
  [ 
    LIMIT <expression>
    [ 
      { OFFSET | , }
      <expression> 
    ]
  ] 
} | SCOPE_IDENTITY() 

<expression> ::=
  | <column_reference>
  | @ <parameter> 
  | ?
  | COUNT( * | { [ DISTINCT ] <expression> } )
  | { AVG | MAX | MIN | SUM | COUNT } ( <expression> ) 
  | NULLIF ( <expression> , <expression> ) 
  | COALESCE ( <expression> , ... ) 
  | CASE <expression>
      WHEN { <expression> | <search_condition> } THEN { <expression> | NULL } [ ... ]
    [ ELSE { <expression> | NULL } ]
    END 
  | <literal>
  | <sql_function> 

<search_condition> ::= 
  {
    <expression> { = | > | < | >= | <= | <> | != | LIKE | NOT LIKE | IN | NOT IN | IS NULL | IS NOT NULL | AND | OR | CONTAINS | BETWEEN } [ <expression> ]
  } [ { AND | OR } ... ] 

Examples

  1. Return all columns:
    SELECT * FROM Users
  2. Rename a column:
    SELECT [Email] AS MY_Email FROM Users
  3. Cast a column's data as a different data type:
    SELECT CAST(Size AS VARCHAR) AS Str_Size FROM Users
  4. Search data:
    SELECT * FROM Users WHERE UserLogin = 'mojombo';
  5. Return the number of items matching the query criteria:
    SELECT COUNT(*) AS MyCount FROM Users 
  6. Return the number of unique items matching the query criteria:
    SELECT COUNT(DISTINCT Email) FROM Users 
  7. Return the unique items matching the query criteria:
    SELECT DISTINCT Email FROM Users 
  8. Summarize data:
    SELECT Email, MAX(Size) FROM Users GROUP BY Email
    See Aggregate Functions for details.
  9. Retrieve data from multiple tables.
    SELECT Commits.AuthorName, CommitComments.Body FROM Commits, CommitComments WHERE Commits.Sha=CommitComments.CommitSha
    See JOIN Queries for details.
  10. Sort a result set in ascending order:
    SELECT Name, Email FROM Users  ORDER BY Email ASC
  11. Restrict a result set to the specified number of rows:
    SELECT Name, Email FROM Users LIMIT 10 
  12. Parameterize a query to pass in inputs at execution time. This enables you to create prepared statements and mitigate SQL injection attacks.
    SELECT * FROM Users WHERE UserLogin = @param
See Explicitly Caching Data for information on using the SELECT statement in offline mode.

Pseudo Columns

Some input-only fields are available in SELECT statements. These fields, called pseudo columns, do not appear as regular columns in the results, yet may be specified as part of the WHERE clause. You can use pseudo columns to access additional features from GraphQL.

    SELECT * FROM Users WHERE Pseudo = '@Pseudo'
    

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Build 21.0.7940