-----Original Message-----
From: Godshall Michael
Sent: Thursday, November 13, 2003 11:42 AM
To: 'Markus Espenhain'
Subject: RE: [ADMIN] SQL-Statement
How many records are their total in Daten, Monatsbeitrag? Maybe 99% of the rows in the table have Daten.ewmanfrdat set to NULL. With all the conditions joined using an AND if one of those fields doesn't match postgresql wouldn't need to look at the rest of the fields before going on to the next row. That would cause the query to run much faster.
-----Original Message-----
From: Markus Espenhain [mailto:espenhain@etes.de]
Sent: Thursday, November 13, 2003 11:23 AM
To: Postgres
Subject: [ADMIN] SQL-Statement
Hello,
sorry for my previos mail.
This was a mistake...
I have an problem with the following statement.
This one works fine and give me the results in just a few seconds.
SELECT Monatsbeitrag.lfdid, Daten.Kundennummer FROM Daten, Monatsbeitrag WHERE ((((Daten.Vetrag widerufen = 2 ) AND NOT((Daten.ewmanfrdat IS NULL ) ) ) AND (Monatsbeitrag.ID = Daten.Kundennummer ) ) AND (((Monatsbeitrag.Monat + 14 ) = '2003-10-27 00:00:00'::timestamp ) AND (Monatsbeitrag.Bezahlt = 2 ) ) ) ORDER BY Daten.Name;
When I edit the statement and delete the "NOT" before "Daten.ewmanfrdat IS NULL" the Query works over 15 Minutes.
SELECT Monatsbeitrag.lfdid, Daten.Kundennummer FROM Daten, Monatsbeitrag WHERE ((((Daten.Vetrag widerufen = 2 ) AND ((Daten.ewmanfrdat IS NULL ) ) ) AND (Monatsbeitrag.ID = Daten.Kundennummer )
) AND (((Monatsbeitrag.Monat + 14 ) = '2003-10-27 00:00:00'::timestamp ) AND (Monatsbeitrag.Bezahlt = 2 ) ) ) ORDER BY Daten.Name;
OK, to select a lot of records it works a time, but for only 350 records?
Where is my problem?
Can anybody help me please.
Regards
Markus
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Markus Espenhain Fon: +49 (7 11) 48 90 83 - 0
ETES - EDV-Systemhaus GbR Fax: +49 (7 11) 48 90 83 - 50
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