On 2/13/07, Tom Lane <tgl@xxxxxxxxxxxxx> wrote:
bitmapqualorig = list_difference_ptr(bitmapqualorig, qpqual); What's not immediately clear is why the condition was in both lists to start with. Perhaps idx_lieu_parking is a partial index with this as its WHERE condition?
Yes, it is: "idx_lieu_parking" btree (parking) WHERE parking = true . Sorry for not pointing it immediatly. If not, the index is not used at all (there are very few lines in lieu with parking=true). So the basic explanation is that it's in both lists due to the partial index and only qpqual keeps the condition? I would have expected the opposite but it doesn't change anything I suppose? Thanks for your answer. -- Guillaume