[Progress Communities] [Progress OpenEdge ABL] Forum Post: RE: Compare SQL query with ABL query, usage of the indexes

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gus bjorklund

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The SQL query processor uses completely different algorithms for deciding which indexes to use than the 4GL does. Among other things, it uses statistics of the number of rows, key distributions, and other info in its choices. You can find out what the query tree looks like by querying the _Sql_Qplan table. its contents are slightly difficult to understand at firsat, but not too bad when you get used to it.

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