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SingleStoreDB v8.1

UNION

Combines results from multiple SELECT statements.

UNION DISTINCT removes duplicate rows, while UNION ALL does not remove them. UNION is equivalent to UNION DISTINCT.

Syntax

SELECT ...
UNION [ALL | DISTINCT] SELECT ...
[UNION [ALL | DISTINCT] SELECT ...]

Remarks

  • The first and all subsequent SELECT statements must select the same number of columns.

Examples

SELECT * FROM table_a UNION ALL SELECT * FROM table_b;
SELECT * FROM table_a UNION SELECT * FROM table_b;

SELECT * FROM id_t UNION ALL SELECT * FROM id_t2;
****
 +------+----------------------------------------------------------------------------+
 | a    | b                                                                          |
 +------+----------------------------------------------------------------------------+
 |    1 | 0xE82C75FA86974BE7903270F4353D865C                                         |
 |    1 | 0x31343865306665352D666666322D346363362D383634622D313838303637313135653236 |
 +------+----------------------------------------------------------------------------+
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