select * from f3002
where ixkitl='CR02CB(2+2)DWKL'

select litm from old02 where litm='CR02CB(2+2)DWKL'

select * from f3002
where ixkitl =(select litm from old02 where litm='CR02CB(2+2)DWKL');

select * from f3002
where ixkitl in (select litm from old02 where litm='CR02CB(2+2)DWKL');

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探讨

SQL code

select * from f3002
where ixkitl in (select litm from old02 where litm='CR02CB(2+2)DWKL');


------解决方案--------------------

子查询要用In，不要直接用那个等号，
select * from f3002
where ixkitl in (select litm from old02 where litm='CR02CB(2+2)DWKL');

仔细检查一下ixkitl与litm是不是对应的？