sql中如果删除表中的记录,从另一表中取条件,那这两个表必须是主
外键的关系:
比如:
create table AA
(
aaID int
primary key,
aaDate varchar(50),
)
create table BB
(
bbID int primary key,
bbName varchar(50),
bbaa int foreign key references AA(aaID )
)
假如AA有10条数据 ,BB有10条数据 ,删除BB中bbaa的某一条数据
delete bb where bbID in (select aaID from AA where aaDate <'2013-01-01')