PostgreSQL create readonly user for all database（创建一个 readonly 的用户，并给予对所有表的只读权限）

grant-pg-readonly-user.sql

-- Create a final user with password
CREATE USER "readonly-user" WITH PASSWORD '123456';

-- 选择一个数据库，后面的权限制定是对单个库有效的

-- Grant access to existing tables
GRANT USAGE ON SCHEMA public TO "readonly-user";
GRANT SELECT ON ALL TABLES IN SCHEMA public TO "readonly-user";
GRANT SELECT ON ALL SEQUENCES IN SCHEMA public TO "readonly-user";

-- Grant access to future tables
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO "readonly-user";