REPLACE

从语义上看，REPLACE 语句是 DELETE 语句和 INSERT 语句的结合，可用于简化应用程序代码。

语法图

ReplaceIntoStmt

REPLACE - 图1

PriorityOpt

REPLACE - 图2

IntoOpt

REPLACE - 图3

TableName

REPLACE - 图4

PartitionNameListOpt

REPLACE - 图5

InsertValues

REPLACE - 图6

1. ReplaceIntoStmt ::=
2. 'REPLACE' PriorityOpt IntoOpt TableName PartitionNameListOpt InsertValues

4. PriorityOpt ::=
5. ( 'LOW_PRIORITY' | 'HIGH_PRIORITY' | 'DELAYED' )?

7. IntoOpt ::= 'INTO'?

9. TableName ::=
10. Identifier ( '.' Identifier )?

12. PartitionNameListOpt ::=
13. ( 'PARTITION' '(' Identifier ( ',' Identifier )* ')' )?

15. InsertValues ::=
16. '(' ( ColumnNameListOpt ')' ( ValueSym ValuesList | SelectStmt | '(' SelectStmt ')' | UnionStmt ) | SelectStmt ')' )
17. |   ValueSym ValuesList
18. |   SelectStmt
19. |   UnionStmt
20. |   'SET' ColumnSetValue? ( ',' ColumnSetValue )*

示例

1. CREATE TABLE t1 (id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, c1 INT NOT NULL);

1. Query OK, 0 rows affected (0.12 sec)

1. INSERT INTO t1 (c1) VALUES (1), (2), (3);

1. Query OK, 3 rows affected (0.02 sec)
2. Records: 3  Duplicates: 0  Warnings: 0

1. SELECT * FROM t1;

1. +----+----+
2. | id | c1 |
3. +----+----+
4. |  1 |  1 |
5. |  2 |  2 |
6. |  3 |  3 |
7. +----+----+
8. 3 rows in set (0.00 sec)

1. REPLACE INTO t1 (id, c1) VALUES(3, 99);

1. Query OK, 2 rows affected (0.01 sec)

1. SELECT * FROM t1;

1. +----+----+
2. | id | c1 |
3. +----+----+
4. |  1 |  1 |
5. |  2 |  2 |
6. |  3 | 99 |
7. +----+----+
8. 3 rows in set (0.00 sec)

MySQL 兼容性

REPLACE 语句与 MySQL 完全兼容。如发现任何兼容性差异，请尝试 TiDB 支持资源。

另请参阅