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Base de données, Tables, Vues, Index et syntaxe SQL
>>The answer depends on how big the tables are and the types of joins involved. Gnerally, three table joins will not cause problems. I think VFP supports up to seven table joins. In my experience, however, I have found that eanything over three tables tends to impact performance. The best thing to do is test each scenario and decide for yourself.
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>It allows ten joins (and it took me twenty long minutes to discover what was wrong when I added four more cursors to join to, because the error message was sort of "suboptimally clear", as Microsoft would put it).
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>IMO, any single scenario may play differently, depending on size of the tables, the compactness of the indexes etc. My rule-of-thumb is to pull the smallest possible cursor from the largest table first, and then join that to the rest. But then, I'm usually having one large table to join to several small lookups (most of the joins I'm dealing with are used to create flat tables for Crystal Reports) so this works for me most of the time.
Thanks for clearing that up!
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