Finding duplicated values

I have a few tables that have duplicated values from an import from a
different database. I have two keys I tried to set as primary and got an
error
ERROR: could not create unique index
DETAIL: Table contains duplicated values.

Is there some join I can use to compare the hmhmkey, wmwmkey pairs against
the table to find duplicate values? Each pair key should be unique but the
old database was less than normalized.

I was trying to use the code below but it returned no rows.

SELECT hmhmkey, wmwmkey
FROM exceptions
EXCEPT
SELECT hmhmkey, wmwmkey
FROM exceptions;

Any suggestions?

Kent Anderson
EZYield.com
407-629-0900
www.ezyield.com

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Kent Anderson wrote:
> I have a few tables that have duplicated values from an import from a
> different database. I have two keys I tried to set as primary and got an
> error
> ERROR: could not create unique index
> DETAIL: Table contains duplicated values.
>
> Is there some join I can use to compare the hmhmkey, wmwmkey pairs
> against the table to find duplicate values? Each pair key should be
> unique but the old database was less than normalized.
>
> I was trying to use the code below but it returned no rows.
>
> SELECT hmhmkey, wmwmkey
> FROM exceptions
> EXCEPT
> SELECT hmhmkey, wmwmkey
> FROM exceptions;
>
> Any suggestions?
>
> Kent Anderson
> EZYield.com
> 407-629-0900
> www.ezyield.com <http://www.ezyield.com/>

Try http://archives.postgresql.org/pgsql-sql/1999-03/msg00239.php

On Thu, 21 Oct 2004, Kent Anderson wrote:

> I have a few tables that have duplicated values from an import from a
> different database. I have two keys I tried to set as primary and got an
> error
> ERROR: could not create unique index
> DETAIL: Table contains duplicated values.
>
> Is there some join I can use to compare the hmhmkey, wmwmkey pairs against
> the table to find duplicate values? Each pair key should be unique but the
> old database was less than normalized.

Maybe
SELECT hmhmkey, wmwmkey
FROM exceptions
GROUP BY hmhmkey, wmwmkey
HAVING count(*)>1;

Kent Anderson wrote:

> I have a few tables that have duplicated values from an import from a
> different database. I have two keys I tried to set as primary and got
> an error
> ERROR: could not create unique index
> DETAIL: Table contains duplicated values.
>
> Is there some join I can use to compare the hmhmkey, wmwmkey pairs
> against the table to find duplicate values? Each pair key should be
> unique but the old database was less than normalized.
>
> I was trying to use the code below but it returned no rows.
>
> SELECT hmhmkey, wmwmkey
> FROM exceptions
> EXCEPT
> SELECT hmhmkey, wmwmkey
> FROM exceptions;
>
> Any suggestions?
>
> Kent Anderson
> EZYield.com
> 407-629-0900
> www.ezyield.com <http://www.ezyield.com/>
>
> ========================================
> This electronic message transmission contains information from the
> Company that may be proprietary, confidential and/or privileged. The
> information is intended only for the use of the individual(s) or
> entity named above. If you are not the intended recipient, be aware
> that any disclosure, copying or distribution or use of the contents of
> this information is prohibited. If you have received this electronic
> transmission in error, please notify the sender immediately by
> replying to the address listed in the "From:" field.
>

******************************
This might do it...
If you do this on the table that had duplicates you wont need to join
select count(hmhmkey),count(wmwmkey) from
exceptions group by hmhmkey,wmwmkey having count(hmhmkey) >1 or having
count(wmwmkey) >1;

Kent Anderson wrote:

> I have a few tables that have duplicated values from an import from a
> different database. I have two keys I tried to set as primary and got
> an error ERROR: could not create unique index
> DETAIL: Table contains duplicated values.Is there some join I can use
> to compare the hmhmkey, wmwmkey pairs against the table to find
> duplicate values? Each pair key should be unique but the old database
> was less than normalized.I was trying to use the code below but it
> returned no rows.SELECT hmhmkey, wmwmkey
> FROM exceptions
> EXCEPT
> SELECT hmhmkey, wmwmkey FROM exceptions;Any suggestions?Kent
> Anderson

You might want to search the [SQL] archive on the following topics
for more inspiration:

selecting duplicate records
Delete 1 Record of 2 Duplicate Records

Regards, Christoph