Github user xuchuanyin commented on the issue:
https://github.com/apache/carbondata/pull/2665
@ravipesala I do think assembling expressions and forward them to the
corresponding datamap is a good idea. But current implementation needs more
work to achieve this goal. We can not just pass the expressions to datamaps and
let the datamap do the dirty work to do intersection or union of each
expression.
As you mentioned we can create multiple individual datamaps, this will also
be a problem now. For example bloomfilter datamap only support 'equalTo' and
'in', but current DataMapChooser will forward 'NotEqual','Greater','Less'... to
the datamap also, which will cause performance waste.
Besides, for both BloomFilter datamap and Lucene datamap, we never treat
specifying multiple columns in 'index_columns' as composite index, actually we
just index them individually.
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