20181218-PostgreSQL数据库Extension管理

注意：在集群的一个数据库中安装扩展，在集群的另一个数据库要使用的话，仍需安装

1. 查看当前已安装Extension

postgres=# \dx
List of installed extensions
Name | Version | Schema | Description
---------+---------+------------+------------------------------
plpgsql | 1.0 | pg_catalog | PL/pgSQL procedural language
(1 row)

2. 查看当前服务器可用的Extension扩展列表

postgres=# select name from pg_available_extensions;
name
--------------------
adminpack
seg
autoinc
dict_xsyn
pg_prewarm
ltree
ltree_plpython2u
bloom
pg_stat_statements
...

3. 安装可用的Extension扩展,查看验证

postgres=# create extension pg_stat_statements ;
CREATE EXTENSION
postgres=# \dx
List of installed extensions
Name | Version | Schema | Descr
iption
--------------------+---------+------------+-----------------------------
------------------------------
pg_stat_statements | 1.5 | public | track execution statistics o
f all SQL statements executed
plpgsql | 1.0 | pg_catalog | PL/pgSQL procedural language
(2 rows)

4. 删除Extension扩展，查看验证

postgres=# drop extension pg_stat_statements ;
DROP EXTENSION
postgres=# \x
Expanded display is on.
postgres=# \dx
List of installed extensions
-[ RECORD 1 ]-----------------------------
Name | plpgsql
Version | 1.0
Schema | pg_catalog
Description | PL/pgSQL procedural language