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' PriorityOpt IntoOpt TableName PartitionNameListOpt InsertValues
PriorityOpt ::=
    ( 'LOW_PRIORITY' | 'HIGH_PRIORITY' | 'DELAYED' )?
IntoOpt ::= 'INTO'?
TableName ::=
    Identifier ( '.' Identifier )?
PartitionNameListOpt ::=
    ( 'PARTITION' '(' Identifier ( ',' Identifier )* ')' )?
InsertValues ::=
    '(' ( ColumnNameListOpt ')' ( ValueSym ValuesList | SelectStmt | '(' SelectStmt ')' | UnionStmt ) | SelectStmt ')' )
|   ValueSym ValuesList
|   SelectStmt
|   UnionStmt
|   'SET' ColumnSetValue? ( ',' ColumnSetValue )*

示例

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

Query OK, 0 rows affected (0.12 sec)

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

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

SELECT * FROM t1;

+----+----+
| id | c1 |
+----+----+
|  1 |  1 |
|  2 |  2 |
|  3 |  3 |
+----+----+
3 rows in set (0.00 sec)

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

Query OK, 2 rows affected (0.01 sec)

SELECT * FROM t1;

+----+----+
| id | c1 |
+----+----+
|  1 |  1 |
|  2 |  2 |
|  3 | 99 |
+----+----+
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。

另请参阅

• DELETE
• INSERT
• SELECT
• UPDATE