How will you delete duplicate records from a table?
Answers were Sorted based on User's Feedback
Answer / tharanath.n
delete from table a
where rowid >(select min(rowid) from table b
where a.column = b.column);
| Is This Answer Correct ? | 13 Yes | 5 No |
Answer / ajay kumar ande
question is wrong......records-----files,table-----rows
How will you delete duplicate records(rows) from a table?
pgm=sort
sortin dd dsn=-----
sortout dd dsn=-----
sysin dd *
sort fields=(2,3,ch,a)
sum fields=none ------>eliminates duplicate recs
| Is This Answer Correct ? | 3 Yes | 1 No |
Answer / venkat
delete from emp where ecode IN ( select ecode from emp group by ecode having count(*) >1 )
| Is This Answer Correct ? | 5 Yes | 4 No |
Answer / mehdee
Hi. This is a database design problem, because if you
alowe duplicate rows then you must have at least a column
being like squence number.
| Is This Answer Correct ? | 2 Yes | 2 No |
Answer / naresh.s
in DB2
first we need to know duplicate records in database file
like tmpfilep ,for that
select RRN(A) from tmpfilep A where field='fieldvalue'
here field means any fileld containd tmpfilep and
corresponding value.
once we execute the above query we will get relative record
numbers of each row and remember that numbers
now you can delete records based on these numbers
delete from tmpfilep A where rrn(A) in (234,341,642)
here 234,341,642 are sample record numbers
may be i am correct upto my knowledge.......
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / king
DELETE FROM FILE WHERE FIELD = ALL(SELECT FIELD FROM FILE
GROUP BY FIELD HAVING COUNT(*) > 1)
OR
DELETE FROM FILE WHERE FIELD = ANY(SELECT FIELD FROM FILE
GROUP BY FIELD HAVING COUNT(*) > 1)
| Is This Answer Correct ? | 1 Yes | 7 No |
Answer / s
DELETE FROM TABLE ABC
WHERE COLUMN =
(SELECT COLUMN FROM TABLE ABC
GROUP BY COLUMN
HAVING COUNT(*) > 1);
| Is This Answer Correct ? | 20 Yes | 36 No |
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