There is a big table with "n" of rows and 40 + columns .It
doesn't have primary key.How do you select the primary key.
In other words how do you get the duplicate records.

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There is a big table with "n" of rows and 40 + columns .It doesn't have primary key...

Answer / nithin

Hi
I could possibly think of only one solution without using
group by clause.

create table emp_bkp as select distinct * from employee
drop table employee
rename emp_bkp to employee

Let me know if there is any other possible answer

Is This Answer Correct ?    3 Yes 1 No

There is a big table with "n" of rows and 40 + columns .It doesn't have primary key...

Answer / harikanth

Suppose Table name is Dup_Del with id as a column(consists
10,20,30,10,10,30,20)then

select * from Dup_Del
where rowid not in(select * from
(select min(rowid) from Dup_Del
group by id
);
the above query will give you the duplicate records. if you
want unique records then

select * from Dup_Del
where rowid in(select * from
(select min(rowid) from Dup_Del
group by id
);

Is This Answer Correct ?    0 Yes 0 No

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