PostgreSQL postgres_fdw 跨库查询与推下谓词实践

初始化与服务器映射：CREATE EXTENSION IF NOT EXISTS postgres_fdw; CREATE SERVER remotesrv FOREIGN DATA IMPORTED FROM postgres OPTIONS (host '10.0.0.2', dbname 'app', port '5432'); CREATE USER MAPPING FOR current_user SERVER remotesrv OPTIONS (user 'replicator', password 'secret'); 导入外部模式或定义外部表：IMPORT FOREIGN SCHEMA public LIMIT TO (users, orders) FROM SERVER remotesrv INTO public; CREATE FOREIGN TABLE public.users_remote ( id bigint, name text ) SERVER remotesrv OPTIONS (schema_name 'public', table_name 'users'); 查询与推下验证：EXPLAIN VERBOSE SELECT * FROM public.users_remote WHERE id > 1000;