Re: MySQL Query Puzzle

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Just to add more perspective :

You will have a table with DISTINCT values.

Drop the initial table (better take a back-up); copy from the temporary
table which will have only DISTINCT values.

Regards,
Shreyas

On Mon, Jul 19, 2010 at 7:58 PM, Shreyas Agasthya <shreyasbr@xxxxxxxxx>wrote:

> How about this :
>
> CREATE TEMPORARY TABLE bad_temp1 (id INT,name VARCHAR(20));
> INSERT INTO bad_temp1 (id,name) SELECT DISTINCT id,name FROM SAMPLE;
>
> Regards,
> Shreyas
>
> On Mon, Jul 19, 2010 at 7:31 PM, Richard Quadling <rquadling@xxxxxxxxx>wrote:
>
>> On 19 July 2010 05:44, Peter <peters@xxxxxxxxxxxx> wrote:
>> > Hi All,
>> >
>> > I have a  table which contain's some duplicate rows. I just want to
>> delete
>> > the duplicate records alone
>> > not original records.
>> >
>> > Assume my table as look as below
>> >
>> > column1 column2
>> > 1
>> >        a
>> > 1
>> >        a
>> > 2
>> >        b
>> > 3
>> >        c
>> > 3
>> >        c
>> >
>> >
>> >
>> > i want the above table need  to be as below, After executing the mysql
>> > query.
>> >
>> > column1
>> >        column2
>> > 1
>> >        a
>> > 2
>> >        b
>> > 3
>> >        c
>> >
>> >
>> >
>> >
>> > Thanks in advance..
>> >
>> > Regards
>> > Peter
>> >
>>
>> If your table had a db generated sequential unique identifier (an
>> identity / autoinc), then something along these lines may be what you
>> are looking for ...
>>
>> -- Delete everything except the UniqueIDs we want to keep.
>> DELETE FROM
>>        Table
>> WHERE
>>        UniqueID NOT IN
>>                (
>>                -- Just get the UniqueIDs we want to keep.
>>                SELECT
>>                        UniqueID
>>                FROM
>>                        (
>>                        -- Get the earlist UniqueID for each Col1, Col2,
>> pairing.
>>                        SELECT
>>                                Col1,
>>                                Col2,
>>                                MIN(UniqueID) AS UniqueID
>>                        FROM
>>                                Table
>>                        GROUP BY
>>                                Col1,
>>                                Col2
>>                        )
>>                )
>>
>> UNTESTED!!!!
>>
>> --
>> PHP General Mailing List (http://www.php.net/)
>> To unsubscribe, visit: http://www.php.net/unsub.php
>>
>>
>
>
> --
> Regards,
> Shreyas Agasthya
>



-- 
Regards,
Shreyas Agasthya

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