Re: optimizing SQL's w/ multiple (and variable) range based predicates against very wide table

Oh, I have no preference against bitmaps, but for the range searches I tend to use B*Tree indexes. After all, that is what they were made for. Bitmap indexes are extremely useful for equality predicates with low selectivity and  some equijoins, where the tables are not frequently modified. The OP's example seems to satisfy the low DML requirement, but I am not sure that range scan of bitmap indexes would be a good thing on a huge table. Chris will just have to test.

On 1/26/19 4:35 PM, Andy Sayer wrote:
>
> Perhaps your preference against bitmaps was justified in earlier
> versions but for me they have been hugely beneficial to allow multiple
> unknown predicates be used effectively with indexes (when the
> optimizer does its job well).
>

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Mladen Gogala
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