Problem with update a table

Question

Hi,
--I need to update a table with only  year 2010  data, it looks like this:
update abc_tab set dept_cd = replace(dept_cd, 'HRE','HW')
where dept_cd in (select dept_cd from edu_tab e, edu_lkp l
where l.dept_rnd_cd =e.dept_rnd_cd
and l.fy_cd ='2010');
--when I run above query, it updated all the data in the column , not just  2010 data, but if I do following
(select dept_cd from edu_tab e, edu_lkp l
where l.dept_rnd_cd =e.dept_rnd_cd
and l.fy_cd ='2010');
-- I got only 2010 data, so what did I do wrong on the update statement?
Thanks a lot.
Wendy

Answer 1

data is not correlated based on DEPT_CD,
try this:
update abc_tab abc set abc.dept_cd = replace(abc.dept_cd, 'HRE','HW')
where abc.dept_cd in (select e.dept_cd
                      from   edu_tab e
                            ,edu_lkp l
                      where  l.dept_rnd_cd = e.dept_rnd_cd
                      and    e.dept_cd     = abc.dept_cd
                      and    l.fy_cd       = '2010'
commit
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