"Nigel J. Andrews" <nandrews(at)investsystems(dot)co(dot)uk> writes:
> could you restate whether an index built with the order b,a would be a good
> candidate for use in a query using a where clause of b = x AND a IN (long
> list) please?
Such an index would only be matched to the b = x clause.
If you can think of a way to improve that without materially increasing
the search time in indxpath.c, I'm all ears...
regards, tom lane