我试图将datetime转换为时间戳，但是mysql给我警告，并且转换的值是错误的。这里是SQL查询
UPDATE table1 A, table2 B SET B.date_added=UNIX_TIMESTAMP(STR_TO_DATE(A.date_added, '%M %d %Y %h:%i%p')) WHERE =;
警告
+---------+------+--------------------------------------------------------------------------+
| Level | Code | Message |
+---------+------+--------------------------------------------------------------------------+
| Warning | 1411 | Incorrect datetime value: '2011-06-11 20:29:02' for function str_to_date |
+---------+------+--------------------------------------------------------------------------+
结果
+---------------------+---------------------+
| date_added | date_added |
+---------------------+---------------------+
| 2012-02-23 06:12:45 | 2012-12-23 19:08:33 |
+---------------------+---------------------+
我也尝试了以下查询，但在时间戳字段中显示0000-00-00 00:00:00。
UPDATE table1 A, table2 B SET B.date_added=UNIX_TIMESTAMP(A.date_added) WHERE =;