求一sql语句！

Question

update aaa set depart=(case when substr(depart,-3,3)='xxx' then replace(depart,'xxx','') 
                            when substr(depart,-2,2)='yy' then replace(depart,'yy','') 
                            else depart end) where substr(depart,-3,3)='xxx' or substr(depart,-2,2)='yy';

Answer 1

update tab1 set 
depart = replace(replace(depart,'xxx',''),'yy','')
where instr(depart,'xxx')>0 or instr(depart,'yy')>0

Answer 2

楼上网友的语句是把所有包含'xxx','yy'的都更新了,包括结尾是'xxx','yy'的记录.update aaa a set a.depart=
decode(substr(a.depart,length(a.depart)-3+1,3),'xxx',
       replace(a.depart,'xxx',''),
       substr(a.depart,length(a.depart)-2+1,2),'yy',
       replace(a.depart,'yy',''),
       a.depart)
where 
     substr(a.depart,length(a.depart)-3+1,3)='xxx'
     or 
     substr(a.depart,length(a.depart)-2+1,2)='yy'

Answer 3

update tbName 
set depart = replace(replace(depart,'xxx',''),'yy','')
where depart like '%xxx' or depart like '%yy';