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Merge statement
function benefits: 1) provides the ability to conditionally update, insert or delete data into a database table. 2) performs an update if the row exists, and an insert if it is a new row. --> 1) avoids seperate updates, 2) increase performance and ease of use. 3) is useful in dat ......
PairWise subquery:
e.g.:
select * from wf_docsort where (ndocsortid,nmoduleinfoid) in (select ndocsortid, nmoduleinfoid from wf_docsort where instr(cname,'ÎÄ')>0)
the above sql is the same function as:
select * from wf_docsort where ndocsortid = (select ndocsortid from wf_docsort where ......