你这个写法没什么大问题,但是一般情况下建议加一个条件:
update si3.per_Reg a set a.cjgzrq=(select b.cbrq from si0001.wqg20141005 b where a.ryid=b.ryid)
where exists(select * from si0001.wqg20141005 b where a.ryid=b.ryid)
update si3.per_Reg a set a.cjgzrq=(select b.cbrq from si0001.wqg20141005 b where a.ryid=b.ryid)
where exists(select * from si0001.wqg20141005 b where a.ryid=b.ryid)
报这个提示 能帮忙分析下什么原因吗
update si3.per_Reg a set a.cjgzrq=(select min(b.cbrq) from si0001.wqg20141005 b where a.ryid=b.ryid)
where exists(select 1 from si0001.wqg20141005 b where a.ryid=b.ryid)