有两个表t1和t2,表中只有一个字段c1。
求两个表的差。即存在于t1,但不存在于t2中的记录。
select c1 from t1 where c1 not in (select c1 from t2)
select c1 from t1 where not exists(select * from t2 where t1.c1=t2.c1)
select t1.c1 from t1 left join t2 on t1.c1=t2.c1 where t2.c1 is null
有两个表t1和t2,表中只有一个字段c1。
求两个表的差。即存在于t1,但不存在于t2中的记录。
select c1 from t1 where c1 not in (select c1 from t2)
select c1 from t1 where not exists(select * from t2 where t1.c1=t2.c1)
select t1.c1 from t1 left join t2 on t1.c1=t2.c1 where t2.c1 is null