我想每天晚上把一张表的数据备份到另外一张备份表中,2张表的结构完全一样,条件是7天以前的数据都备份过去,条件该怎么写?
AS
BEGIN--备份数据。
insert into message_detail_copy select * from message_detail
where message_detail.sendtime < SYSDATE?????? ;
commit ;--删除备份过的数据。
delete from message_detail where message_detail.sendtime < SYSDATE?????? ;
commit ;END p_trans_message ;
AS
BEGIN--备份数据。
insert into message_detail_copy select * from message_detail
where message_detail.sendtime < SYSDATE?????? ;
commit ;--删除备份过的数据。
delete from message_detail where message_detail.sendtime < SYSDATE?????? ;
commit ;END p_trans_message ;
where message_detail.sendtime < trunc(SYSDATE)-7 ;
commit ;--删除备份过的数据。
delete from message_detail where message_detail.sendtime < trunc(SYSDATE)-7 ;
commit ;