PostgreSQL的OID类型是什么

这篇文章主要介绍"PostgreSQL的OID类型是什么"，在日常操作中，相信很多人在PostgreSQL的OID类型是什么问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答"PostgreSQL的OID类型是什么"的疑惑有所帮助！接下来，请跟着小编一起来学习吧！

OID定义为无符号整型数字,PG内置了转换函数从regproc, regprocedure, regoper, regoperator, regclass, regtype, regrole, regnamespace, regconfig, and regdictionary这些类型转换为OID.

TODO

下面是一些例子:
查询某张表的属性

[local]:5432 pg12@testdb=# SELECT * FROM pg_attribute  WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'tbl') limit 1;-[ RECORD 1 ]-+---------attrelid      | 32774attname       | tableoidatttypid      | 26attstattarget | 0attlen        | 4attnum        | -6attndims      | 0attcacheoff   | -1atttypmod     | -1attbyval      | tattstorage    | pattalign      | iattnotnull    | tatthasdef     | fatthasmissing | fattidentity   | attgenerated  | attisdropped  | fattislocal    | tattinhcount   | 0attcollation  | 0attacl        | attoptions    | attfdwoptions | attmissingval | Time: 5.209 ms-->[local]:5432 pg12@testdb=# SELECT * FROM pg_attribute where attrelid = 'tbl'::regclass limit 1;-[ RECORD 1 ]-+---------attrelid      | 32774attname       | tableoidatttypid      | 26attstattarget | 0attlen        | 4attnum        | -6attndims      | 0attcacheoff   | -1atttypmod     | -1attbyval      | tattstorage    | pattalign      | iattnotnull    | tatthasdef     | fatthasmissing | fattidentity   | attgenerated  | attisdropped  | fattislocal    | tattinhcount   | 0attcollation  | 0attacl        | attoptions    | attfdwoptions | attmissingval | Time: 1.205 ms

查询操作符+的相关信息

[local]:5432 pg12@testdb=# select * from pg_operator where oid='+(int,float)'::regoperator;ERROR:  operator does not exist: +(int,float)LINE 1: select * from pg_operator where oid='+(int,float)'::regopera...                                            ^Time: 1.502 ms[local]:5432 pg12@testdb=# select * from pg_operator where oid='+(float,float)'::regoperator;-[ RECORD 1 ]+---------oid          | 591oprname      | +oprnamespace | 11oprowner     | 10oprkind      | boprcanmerge  | foprcanhash   | foprleft      | 701oprright     | 701oprresult    | 701oprcom       | 591oprnegate    | 0oprcode      | float8ploprrest      | -oprjoin      | -Time: 3.446 ms

注意:操作符需指定参数.

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