Svein Erling Tysvær wrote:

>>Primary Key Stats (PK_SKU_STORE). 0.0000004474044
>>Store_No Key Stats (IDX_STORE). 0.5000000000000
>
> Drop the index on Store_No, the selectivity is too poor for the index
> to be useful (your GROUP BY query should execute somewhat faster
> without this index, probably equal to your DISTINCT query).

And why doesn't FB automatically ignore an index with such bad
selectivity in this situation? Is there *any* situation where this index
should actually be used? I doubt it. So the engine should ignore it.

This is just one example of a performance pitfall with FB that could
probably be fixed.

Kjell
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Kjell Rilbe
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