[bdbxml] queries with mixed (index/non) predicate expressions do not benefit from indexing

Hi:

 

I am new to dbxml, but planning to do extensive use of indexes (and will need their performance).

Over a container of about 20000 docs, I could observe that "edge" indexing

of elements brings the expected speed gain: query time on an "edge-element-equal-string" indexed element is roughly proportional to the number of docs for this entry,

as opposed to the total number of docs (when no index).

 

However, I notice no gain for XPath that uses a predicate _expression_, mixing some

indexed element with non-indexed element, e.g.:

 

Assuming an edge-element-equal-string on "Town" element, a query using XPath:

 

...Location[Town='Solana']

 

will benefit from the indexing, while:

 

...Location[State='CA'  and Town='Solana']

 

seems to NOT optimize at all (does not make use of index on Town) and has a query time roughly same as if no index at all on Town.

 

Any plan to fix this? (and apologies if this is already reported, could not acess bug databse)

 

Thanks,

 

Jacques Durand