postgres_fdw操作

pg自带postgres_fdw插件，无需额外安装。

1. 增

创建postgres_fdw插件

CREATE EXTENSION postgres_fdw;

创建foreign server

CREATE SERVER foreign_server
        FOREIGN DATA WRAPPER postgres_fdw
        OPTIONS (host '192.83.123.89', port '5432', dbname 'foreign_db');

创建user mapping

CREATE USER MAPPING FOR local_user
        SERVER foreign_server
        OPTIONS (user 'foreign_user', password 'password');

创建foreign table

CREATE FOREIGN TABLE foreign_table (
        id integer NOT NULL,
        data text
)
        SERVER foreign_server
        OPTIONS (schema_name 'some_schema', table_name 'some_table');

2. 删

删除foreign table

DROP FOREIGN TABLE foreign_table;

删除user mapping

DROP USER MAPPING [ IF EXISTS ] FOR { user_name | USER | CURRENT_USER | PUBLIC } SERVER server_name;

删除 foreign server

DROP SERVER foreign_server;

3. 改

修改foreign server配置

ALTER SERVER foo OPTIONS (host 'foo', dbname 'foodb');

ALTER SERVER foo VERSION '8.4' OPTIONS (SET host 'baz');

修改user mapping

ALTER USER MAPPING FOR bob SERVER foo OPTIONS (user 'bob', password 'public');

修改foreign table

ALTER FOREIGN TABLE distributors ALTER COLUMN street SET NOT NULL;

ALTER FOREIGN TABLE myschema.distributors OPTIONS (ADD opt1 'value', SET opt2, 'value2', DROP opt3 'value3');

4. 查

查看 foreign server

SELECT * FROM pg_foreign_server;

查看user mapping

SELECT * FROM pg_user_mappings;