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 driver:

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 incident

2. Rename a column:
   

   SELECT [priority] AS MY_priority FROM incident

3. Cast a column's data as a different data type:
   

   SELECT CAST(priority AS VARCHAR) AS Str_priority FROM incident

4. Search data:
   

   SELECT * FROM incident WHERE category = 'request'

5. Return the number of items matching the query criteria:
   

   SELECT COUNT(*) AS MyCount FROM incident 

6. Return the number of unique items matching the query criteria:
   

   SELECT COUNT(DISTINCT priority) FROM incident 

7. Return the unique items matching the query criteria:
   

   SELECT DISTINCT priority FROM incident 

8. Summarize data:
   

   SELECT priority, MAX(priority) FROM incident GROUP BY priority

   See Aggregate Functions for details.
9. Retrieve data from multiple tables.
   

   SELECT incident.close_notes, system_user.name FROM incident INNER JOIN system_user ON incident.caller_id = system_user.system_id

   See JOIN Queries for details.
10. Sort a result set in ascending order:
    

    SELECT sys_id, priority FROM incident  ORDER BY priority ASC

11. Restrict a result set to the specified number of rows:
    

    SELECT sys_id, priority FROM incident 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 incident WHERE category = @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 ServiceNow.

    SELECT * FROM incident WHERE Pseudo = '@Pseudo'