Guilherme wrote:
>I have 3 tables tableA, tableB and tableC and the fields tableA.id,
>tableB.idA and tableC.idA.
>I'm using this query (bellow) to call information from the database that has
>in tableA but tableA.id is not found on tableB.idA and tableC.idA.
>
>SELECT tableA.*
> FROM tableA
> LEFT JOIN tableB ON (tableB.idA = tableA.id)
> LEFT JOIN tableC ON (tableC.idA = tableA.id)
> WHERE tableB.idA IS NULL AND tableC.idA IS NULL;
>
>With a low ammount of data (30 records) I receive the data really fast.
>However with a greater ammount of data (1800 records) it takes 26 seconds to
>return data and it consumes 100% of processor. This situation happens when I
>have all tableA.id registered on tableB.ida or tableC.ida.
>
>Any ideas?
>
>
>
Of course you have indexes on all of the id, idA, idB columns?
Greetings
Ralf
sql, query
--
Ralf Narozny
SPLENDID Internet GmbH & Co KG
Skandinaviendamm 212, 24109 Kiel, Germany
fon: +49 431 660 97 0, fax: +49 431 660 97 20
mailto:[EMAIL PROTECTED], http://www.splendid.de
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