数据库删除指定日期以前的数据

delete from 表名 where cast(字段名 as datetime)<'2009-07-21';
commit;


delete from eip_user where cast (create_time as datetime)<'2019-08-04';
commit;


delete from allTData where crt_time<'2017-05-31 00:00:00'

这是删除指定日期2017年5月31日0点之后的数据