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  • REPLACE替换语句

    REPLACE [LOW_PRIORITY | DELAYED]
        [INTO] tbl_name
        [PARTITION (partition_name [, partition_name] ...)]
        [(col_name [, col_name] ...)]
        {VALUES | VALUE} (value_list) [, (value_list)] ...
    
    REPLACE [LOW_PRIORITY | DELAYED]
        [INTO] tbl_name
        [PARTITION (partition_name [, partition_name] ...)]
        SET assignment_list
    
    REPLACE [LOW_PRIORITY | DELAYED]
        [INTO] tbl_name
        [PARTITION (partition_name [, partition_name] ...)]
        [(col_name [, col_name] ...)]
        SELECT ...
    
    value:
        {expr | DEFAULT}
    
    value_list:
        value [, value] ...
    
    assignment:
        col_name = value
    
    assignment_list:
        assignment [, assignment] ...

    https://dev.mysql.com/doc/refman/5.7/en/replace.html

    CREATE TABLE test (
      id INT UNSIGNED NOT NULL AUTO_INCREMENT,
      data VARCHAR(64) DEFAULT NULL,
      ts TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
      PRIMARY KEY (id)
    );
    mysql> REPLACE INTO test VALUES (1, 'Old', '2014-08-20 18:47:00');
    Query OK, 1 row affected (0.04 sec)
    
    mysql> REPLACE INTO test VALUES (1, 'New', '2014-08-20 18:47:42');
    Query OK, 2 rows affected (0.04 sec)
    
    mysql> SELECT * FROM test;
    +----+------+---------------------+
    | id | data | ts                  |
    +----+------+---------------------+
    |  1 | New  | 2014-08-20 18:47:42 |
    +----+------+---------------------+
    1 row in set (0.00 sec)
    CREATE TABLE test2 (
      id INT UNSIGNED NOT NULL AUTO_INCREMENT,
      data VARCHAR(64) DEFAULT NULL,
      ts TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
      PRIMARY KEY (id, ts)
    );
    mysql> REPLACE INTO test2 VALUES (1, 'Old', '2014-08-20 18:47:00');
    Query OK, 1 row affected (0.05 sec)
    
    mysql> REPLACE INTO test2 VALUES (1, 'New', '2014-08-20 18:47:42');
    Query OK, 1 row affected (0.06 sec)
    
    mysql> SELECT * FROM test2;
    +----+------+---------------------+
    | id | data | ts                  |
    +----+------+---------------------+
    |  1 | Old  | 2014-08-20 18:47:00 |
    |  1 | New  | 2014-08-20 18:47:42 |
    +----+------+---------------------+
    2 rows in set (0.00 sec)
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  • 原文地址:https://www.cnblogs.com/wonchaofan/p/13521100.html
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