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Speed problems - getting desperate
Message
De
06/03/1999 01:27:09
Larry Long
ProgRes (Programming Resources)
Georgie, États-Unis
 
 
À
01/03/1999 20:18:13
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00192832
Message ID:
00194796
Vues:
23
>>
>>SELECT Table1.*
>>FROM Table1;
>>INNER JOIN Table2 ;
>>ON Table2.SeqNo=Table1.LinkField ;
>>WHERE Table2.Id="123"
>>
>>I believe that this could speed things up. By selecting all the fields from a table it may not have to create a temp file from scratch (more like a filter on an existing table). Let me know if this does, in fact, work better.
>>HTH
>
>This is true of SQL select statements, even those that SQL select INTO CURSOR. But it is not true of views. Even the simplest view from the smallest table creates its own temp file because the SQL that is actually generated by VFP to create the cursor includes the NOFILTER clause. This is required for views to allow the inherent buffering.
Gotcha...
How about this...wouldn't using the "==" operator help speed things up i.e
WHERE Table2.Id=="123"?

And is there any difference in functionality and/or speed between the above statement and ...
SELECT Table1.*
FROM Table1, Table2 ;
WHERE Table2.SeqNo=Table1.LinkField AND Table2.Id="123" ?
L.A.Long
ProgRes
lalong1@charter.net
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