38.15. Operator Optimization Information

38.15.1. COMMUTATOR
38.15.2. NEGATOR
38.15.3. RESTRICT
38.15.4. JOIN
38.15.5. HASHES
38.15.6. MERGES

+38.15. Operator Optimization Information

38.15. Operator Optimization Information
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38.15. Operator Optimization Information

38.15.1. COMMUTATOR
38.15.2. NEGATOR
38.15.3. RESTRICT
38.15.4. JOIN
38.15.5. HASHES
38.15.6. MERGES

A PostgreSQL operator definition can include several optional clauses that tell the system useful things about how the operator behaves. These clauses should be provided whenever @@ -13,7 +13,7 @@

Additional optimization clauses might be added in future versions of PostgreSQL. The ones described here are all - the ones that release 15.5 understands. + the ones that release 15.6 understands.

It is also possible to attach a planner support function to the function that underlies an operator, providing another way of telling the system @@ -278,4 +278,4 @@ table1.column1 OP table2.column2 The function underlying a merge-joinable operator must be marked immutable or stable. If it is volatile, the system will never attempt to use the operator for a merge join. -

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38.14. User-Defined Operators	Home	38.16. Interfacing Extensions to Indexes