While prefix expression
y like 'abc%'
can be converted to
y >= 'abc'
(see expand_indexqual_opclause()), I'm not sure any kind of expansion is
possible for '%abc%' which would result in a b-tree searchable condition.
Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:
> Is there a fundamental reason the filter on y is not being applied to
> the index scan, rather than the heap scan?
--
Antonin Houska
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