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SQL Join Optimization
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De
06/11/1998 10:22:55
 
 
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Forum:
Visual FoxPro
Catégorie:
Autre
Titre:
SQL Join Optimization
Divers
Thread ID:
00155223
Message ID:
00155223
Vues:
69
I am trying to join a 300K table to one that has
about 5 million records. The 1 to many join is
based on 4 fields. All 4 fields in both tables
are indexed.

Is it best to use the ANSI 92 JOIN ON with all
4 fields combined with an AND or should I use the
WHERE clause? I tried using the SYS(3054,11) command
and am getting 'none' as the optimization level.

What can I do to optimize this join?

The info below represent what I have now:

SELECT tablea.* ;
from tablea aa ;
JOIN tableb bb ;
ON aa.f1 = bb.f1 AND ;
aa.f2 = bb.f2 AND ;
aa.f3 = bb.f3 AND ;
aa.f4 = bb.f4 ;
INTO CURSOR cx
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