SYSTEM CATALOG · 系统目录

pg_pltemplate

The catalog pg_pltemplate stores “template” information for procedural languages. A template for a language allows the language to be created in a particular database by a simple CREATE LANGUAGE command, with no need to specify implementation details. Unlike most system catalogs, pg_pltemplate is shared across all databases of a cluster: there is only one copy of pg_pltemplate per cluster, not one per database. This allows the information to be accessible in each database as it is needed.

首次收录 PG 9.0最近收录 PG 12当前字段 8

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

已与 PostgreSQL 12.22 实例逐字段核对 · 原始实测记录 ↗

字段结构 PostgreSQL 12

pg_pltemplate

字段 / COLUMN	类型 / TYPE	说明 / DESCRIPTION
`tmplname`	`name`NOT NULL	Name of the language this template is for
`tmpltrusted`	`boolean`NOT NULL	True if language is considered trusted
`tmpldbacreate`	`boolean`NOT NULL	True if language may be created by a database owner
`tmplhandler`	`text`NOT NULL	Name of call handler function
`tmplinline`	`text`	Name of anonymous-block handler function, or null if none
`tmplvalidator`	`text`	Name of validator function, or null if none
`tmpllibrary`	`text`NOT NULL	Path of shared library that implements language
`tmplacl`	`aclitem[]`	Access privileges for template (not actually used)

标记“隐式列”的字段不包含在 SELECT * 中；部分早期统计视图由同版本源码补全，额外来源会显示在字段说明中。

通用系统列 6

PostgreSQL 提供的系统属性，通常不在 SELECT * 中展开。单独保留，不与普通字段混算。

字段	类型	attnum
`tableoid`	`oid`	-6
`cmax`	`cid`	-5
`xmax`	`xid`	-4
`cmin`	`cid`	-3
`xmin`	`xid`	-2
`ctid`	`tid`	-1

字段演化矩阵

悬停查看字段类型

存在新增 / 类型或属性变化移除

字段 / COLUMN	13	14	15	16	17	18	19
`tmplname`	−	–	–	–	–	–	–
`tmpltrusted`	−	–	–	–	–	–	–
`tmpldbacreate`	−	–	–	–	–	–	–
`tmplhandler`	−	–	–	–	–	–	–
`tmplinline`	−	–	–	–	–	–	–
`tmplvalidator`	−	–	–	–	–	–	–
`tmpllibrary`	−	–	–	–	–	–	–
`tmplacl`	−	–	–	–	–	–	–

9.0 是收录基线；基线中已存在的字段不标记为新增。矩阵按字段名称对齐，重命名显示为旧字段移除与新字段新增。

演化时间线

相邻大版本的变化

PostgreSQL 13 ← 12移除目录

− tmplname− tmpltrusted− tmpldbacreate− tmplhandler− tmplinline− tmplvalidator− tmpllibrary− tmplacl

PostgreSQL 10 ← 9.6

目录说明更新

PostgreSQL 9.5 ← 9.4

~ tmplhandler: not_null: false → true~ tmpllibrary: not_null: false → true

PostgreSQL 9.1 ← 9.0

1 处字段说明更新

比较任意两个版本

起始版本 / FROM目标版本 / TO包含描述更新

选择两个版本，查看字段的新增、移除与类型变化。交互比较需要 JavaScript；演化时间线可直接阅读。