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 WordPress adapter:
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> ]
} [ , ... ]
[
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> { = | AND | > | < | IN | NOT IN } [ <expression> ]
} [ { AND | OR } ... ]
Examples
- Return all columns:
SELECT * FROM Categories
- Rename a column:
SELECT "Name" AS MY_Name FROM Categories
- Cast a column's data as a different data type:
SELECT CAST(Count AS VARCHAR) AS Str_Count FROM Categories
- Search data:
SELECT * FROM Categories WHERE Id = '1668776136772254'
- The WordPress APIs support the following operators in the WHERE clause: =, AND, >, <, IN, NOT IN.
SELECT * FROM Categories WHERE Id = '1668776136772254';
- Return the number of items matching the query criteria:
SELECT COUNT(*) AS MyCount FROM Categories
- Return the number of unique items matching the query criteria:
SELECT COUNT(DISTINCT Name) FROM Categories
- Return the unique items matching the query criteria:
SELECT DISTINCT Name FROM Categories
- Sort a result set in ascending order:
SELECT Id, Name FROM Categories ORDER BY Name ASC
Aggregate Functions
For SELECT examples using aggregate functions, see Aggregate Functions.
JOIN Queries
See JOIN Queries for SELECT query examples using JOINs.
Date Literal Functions
Date Literal Functions contains SELECT examples with date literal functions.
Window Functions
See Window Functions for SELECT examples containing window functions.
Table-Valued Functions
See Table-Valued Functions for SELECT examples with table-valued functions.