Re: How to find not unique rows in a table? - Mailing list pgsql-general

am  Wed, dem 08.10.2008, um 13:20:47 +0200 mailte A B folgendes:
> Assuming you have a table where some rows have the same values in all
> columnes, how do you find these rows?

You can use the ctid-column:

test=*# select * from dup;
 a | b
---+---
 1 | 1
 1 | 2
 2 | 1
 1 | 1
 3 | 3
 3 | 3
(6 rows)

test=*# select * from dup where (ctid,a,b) not in (select distinct on (a,b) ctid,* from dup);
 a | b
---+---
 1 | 1
 3 | 3
(2 rows)



Andreas
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Andreas Kretschmer
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