| --- |
| title: pg_operator |
| --- |
| |
| <!-- |
| Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you under the Apache License, Version 2.0 (the |
| "License"); you may not use this file except in compliance |
| with the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, |
| software distributed under the License is distributed on an |
| "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| KIND, either express or implied. See the License for the |
| specific language governing permissions and limitations |
| under the License. |
| --> |
| |
| The `pg_operator` system catalog table stores information about operators, both built-in and those defined by `CREATE OPERATOR`. Unused column contain zeroes. For example, `oprleft` is zero for a prefix operator. |
| |
| <a id="topic1__gy150092"></a> |
| <span class="tablecap">Table 1. pg\_catalog.pg\_operator</span> |
| |
| | column | type | references | description | |
| |----------------|---------|-------------------|--------------------------------------------------------------------------------------------------------------------------| |
| | `oprname` | name | | Name of the operator. | |
| | `oprnamespace` | oid | pg\_namespace.oid | The OID of the namespace that contains this operator. | |
| | `oprowner` | oid | pg\_authid.oid | Owner of the operator. | |
| | `oprkind` | char | | `b` = infix (both), `l` = prefix (left), `r` = postfix (right) | |
| | `oprcanhash` | boolean | | This operator supports hash joins. | |
| | `oprleft` | oid | pg\_type.oid | Type of the left operand. | |
| | `oprright` | oid | pg\_type.oid | Type of the right operand. | |
| | `oprresult` | oid | pg\_type.oid | Type of the result. | |
| | `oprcom` | oid | pg\_operator.oid | Commutator of this operator, if any. | |
| | `oprnegate` | | pg\_operator.oid | Negator of this operator, if any. | |
| | `oprlsortop` | oid | pg\_operator.oid | If this operator supports merge joins, the operator that sorts the type of the left-hand operand (`L<L`). | |
| | `oprrsortop` | oid | pg\_operator.oid | If this operator supports merge joins, the operator that sorts the type of the right-hand operand (`R<R`). | |
| | `oprltcmpop` | oid | pg\_operator.oid | If this operator supports merge joins, the less-than operator that compares the left and right operand types (`L<R`). | |
| | `oprgtcmpop` | oid | pg\_operator.oid | If this operator supports merge joins, the greater-than operator that compares the left and right operand types (`L>R`). | |
| | `oprcode` | regproc | pg\_proc.oid | Function that implements this operator. | |
| | `oprrest ` | regproc | pg\_proc.oid | Restriction selectivity estimation function for this operator. | |
| | `oprjoin` | regproc | pg\_proc.oid | Join selectivity estimation function for this operator. | |
| |
| |
| |
| |
