向MYSQL中已插入的日期时间记录插入当前时间减去1小时
要减去日期，请使用MySQLDATE_SUB()。让我们首先创建一个-
mysql> create table DemoTable1434 -> ( -> ArrivalDatetime datetime -> );
使用insert在表中插入一些记录-
mysql> insert into DemoTable1434 values('2019-09-30 21:10:00');
mysql> insert into DemoTable1434 values('2018-09-30 22:20:40');
mysql> insert into DemoTable1434 values('2017-09-30 23:10:00');使用选择显示表中的所有记录-
mysql> select * from DemoTable1434;
这将产生以下输出-
+---------------------+ | ArrivalDatetime | +---------------------+ | 2019-09-30 21:10:00 | | 2018-09-30 22:20:40 | | 2017-09-30 23:10:00 | +---------------------+ 3 rows in set (0.00 sec)
以下是插入当前时间减去1小时的查询。我们将在这里更新-
mysql> update DemoTable1434 -> set ArrivalDatetime=date_sub(now(),interval 1 hour); Rows matched: 3 Changed: 3 Warnings: 0
当前日期时间如下-
mysql> select now(); +---------------------+ | now() | +---------------------+ | 2019-09-30 21:16:48 | +---------------------+ 1 row in set (0.00 sec)
让我们再次检查表记录-
mysql> select * from DemoTable1434;
这将产生以下输出-
+---------------------+ | ArrivalDatetime | +---------------------+ | 2019-09-30 20:16:39 | | 2019-09-30 20:16:39 | | 2019-09-30 20:16:39 | +---------------------+ 3 rows in set (0.00 sec)