Hi gudmrng to all,
This is Sathish.
Q. A table contains 50 records in that 25 recs are duplicate how to delete duplicate records?

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Hello, Which database you are using .. Cheers, Chandra

Dear All.
finding the duplicate records :
select * from emp
where sal in (select sal from emp
group by sal
having count(1)>1);


2.duplicate records deletion:
delete emp
where sal in (select sal from emp
group by sal
having count(1)>1)

Thanks &Regards,
kethinenisarath

Hi,

If your database is oracle then by using ROWID psuedo column you can delete the duplicate records.see below syntax

delete from where rowid not in(select max(rowid) from group by .

eg:i want to delete the duplicate records from emp table.

delete from emp where rowid not in(select max(rowid) from emp group by empno);

Thanks,
vl

DELETE FROM table_name WHERE rowid NOT IN (SELECT max(rowid) FROM table_name GROUP BY id);

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