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

PriorityOpt

IntoOpt

TableName

PartitionNameListOpt

InsertValues

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,请在 GitHub 上提交 issue。
