huge table / bitmap indexes

Hello All

 is  in  postgres  any possibility to create bitmap index ? I have big
 (~12  000  000  records)  table where one field have limited count of
 values.  Many  queries  use this field in where section. I thing that
 bitmap index will by better than BTree.
 How i can optimize select on this table ?

    Thanks - Cure


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The poor player plays the opponent's game for him.
 cure                          mailto:cure@icpnet.pl