RailsでPostgreSQLの情報を確認する

RailsでDB接続する

config/database.ymlに設定した接続情報を元に接続

$ rails dbconsole

db_name=>

postgresのコマンド

データベース一覧

db_name=> \l
                                 List of databases
    Name     |  Owner   | Encoding |   Collate   |    Ctype    | Access privileges 
-------------+----------+----------+-------------+-------------+-------------------
 db_name | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | 
 template0   | user_name   | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/user_name        +
             |          |          |             |             | user_name=CTc/user_name
 template1   | user_name   | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/user_name        +
             |          |          |             |             | user_name=CTc/user_name

ユーザー一覧表示

db_name=> \du
                             List of roles
 Role name |                   Attributes                   | Member of 
-----------+------------------------------------------------+-----------
 postgres  | Create DB                                      | {}
 user_name    | Superuser, Create role, Create DB, Replication | {}

テーブル一覧

db_name=> \d
                      List of relations
 Schema |             Name             |   Type   |  Owner   
--------+------------------------------+----------+----------
 public | groups                       | table    | postgres
 public | groups_id_seq                | sequence | postgres

テーブル定義を確認する

db_name=> \d groups
                                     Table "public.groups"
   Column   |            Type             |                      Modifiers                      
------------+-----------------------------+-----------------------------------------------------
 id         | integer                     | not null default nextval('groups_id_seq'::regclass)
 group_name | character varying           | 
 deleted_at | timestamp without time zone | 
 created_at | timestamp without time zone | not null
 updated_at | timestamp without time zone | not null
Indexes:
    "groups_pkey" PRIMARY KEY, btree (id)

SQL文の実行
SQLをそのまま打ち込み、実行可能。当たり前かw

例 該当するテーブルを削除

db_name=> drop table groups;