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duplicate records
hello i am using oracle & found a new way to find duplicates without mentioning the column names ,please suggest whether it is correct or not (because using order by clause in subquery is of no importance) but i tested it on 2million records n no times and its working :- Select * from (select rownum as r1 , a.* from (select * from test order by 1,2) a) natural join (select rownum+1 as r1 , a.* from (select * from test order by 1,2) a) ; Note: - Null will not come as duplicated records.(for null we can use case staement and aliasing it as 0 )
There are various ways and subquery is one of them though they are expensive. I better prefer HAVING and GROUP BY. the code you have highlighted is not TSQL but PL/SQL.
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