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042c9091f0
The planner simplifies boolean comparisons such as "x = true" and "x = false" down to "x" and "NOT x" respectively, to have a canonical form to ease comparisons. However, if we want to use an index on x, the index AM APIs require us to reconstitute the comparison-operator form of the indexqual. While that works, in bitmap indexscans the canonical form of the qual was emitted as a "filter" condition although it really only needs to be a "recheck" condition, because create_bitmap_scan_plan didn't recognize the equivalence of that form with the generated indexqual. booleq() is pretty cheap so that likely doesn't make very much difference, but it's unsightly so let's clean it up. To fix, add a case to predicate_implied_by() to recognize the equivalence of such clauses. This is a relatively low-cost place to add a check, and perhaps it will have additional use cases in future. Richard Guo and Tom Lane, per discussion of bug #17618 from Sindy Senorita. Discussion: https://postgr.es/m/17618-7a2240bfaa7e84ae@postgresql.org
The PostgreSQL contrib tree
---------------------------
This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
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User documentation for each module appears in the main SGML
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When building from the source distribution, these modules are not
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Some directories supply new user-defined functions, operators, or
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CREATE EXTENSION module_name;
See the PostgreSQL documentation for more information about this
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