PostgreSQL

extensions（扩展）:

查看数据库已安装的扩展:

postgres=# dx
# Output:
#    Name   | Version |   Schema   |                             Description
# ----------+---------+------------+---------------------------------------------------------------------
#  plpgsql  | 1.0     | pg_catalog | PL/pgSQL procedural  language
#  postgis  | 2.4.6   | public     | PostGIS geometry,  geography, and raster spatial types and functions
#  zhparser | 2.1     | public     | a parser for full-text search of Chinese
# (3 rows)

# 或者
postgres=# SELECT * FROM pg_extension;
# 输出跟上面有点 dx 有点不同.

查看数据库可安装的扩展:

postgres=# select * from pg_available_extensions;
# Output:
#             name             | default_version | installed_version |                                                       comment
# ------------------------------+-----------------+-------------------+---------------------------------------------------------------------------------------------------------------------
# refint                       | 1.0             |                   | functions for implementing referential integrity (obsolete)
# postgis                      | 2.4.6           | 2.4.6             | PostGIS geometry, geography, and raster spatial types and functions

Refs:

• Listing the extensions available in PostgreSQL