Heikki Linnakangas <hlinnakan...@vmware.com> writes: > On 08/25/2014 04:48 PM, Tom Lane wrote: >> [ scratches head... ] Surely similar_escape is marked immutable, and >> will therefore be executed exactly once in either of these formulations, >> because the planner will fold the expression to a constant.
> Yeah, just noticed that myself.. ... although, given that, it is also fair to wonder how much the speed of similar_escape really matters. Surely in most use-cases the pattern and escape char will be constants. And, when they are not, wouldn't the subsequent parsing work for the regexes dominate the cost of similar_escape anyway? IOW, I'm not sure we should be advising Jeff to duplicate code in order to have a fast path. Keeping it short might be the best goal. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers