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 IBM Cloud Object Storage adapter:
SELECT {
[ TOP <numeric_literal> | DISTINCT ]
{
*
| {
<expression> [ [ AS ] <column_reference> ]
| { <table_name> | <correlation_name> } .*
} [ , ... ]
}
{
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 | LIKE | IN } [ <expression> ]
} [ { AND | OR } ... ]
Examples
- Return all columns:
SELECT * FROM Objects
- Rename a column:
SELECT "Etag" AS MY_Etag FROM Objects
- Cast a column's data as a different data type:
SELECT CAST(AnnualRevenue AS VARCHAR) AS Str_AnnualRevenue FROM Objects
- Search data:
SELECT * FROM Objects WHERE Bucket = 'testBucket'
- The IBM Cloud Object Storage APIs support the following operators in the WHERE clause: =, AND, LIKE, IN.
SELECT * FROM Objects WHERE Bucket = 'testBucket';
- Return the number of items matching the query criteria:
SELECT COUNT(*) AS MyCount FROM Objects
- Return the number of unique items matching the query criteria:
SELECT COUNT(DISTINCT Etag) FROM Objects
- Return the unique items matching the query criteria:
SELECT DISTINCT Etag FROM Objects
- Sort a result set in ascending order:
SELECT Key, Etag FROM Objects ORDER BY Etag 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.