codigocomentado/migrations/00000000000000_diesel_initi.../up.sql

37 lines
1.1 KiB
PL/PgSQL

-- This file was automatically created by Diesel to setup helper functions
-- and other internal bookkeeping. This file is safe to edit, any future
-- changes will be added to existing projects as new migrations.
-- Sets up a trigger for the given table to automatically set a column called
-- `updated_at` whenever the row is modified (unless `updated_at` was included
-- in the modified columns)
--
-- # Example
--
-- ```sql
-- CREATE TABLE users (id SERIAL PRIMARY KEY, updated_at TIMESTAMP NOT NULL DEFAULT NOW());
--
-- SELECT diesel_manage_updated_at('users');
-- ```
CREATE OR REPLACE FUNCTION diesel_manage_updated_at(_tbl regclass) RETURNS VOID AS $$
BEGIN
EXECUTE format('CREATE TRIGGER set_updated_at BEFORE UPDATE ON %s
FOR EACH ROW EXECUTE PROCEDURE diesel_set_updated_at()', _tbl);
END;
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION diesel_set_updated_at() RETURNS trigger AS $$
BEGIN
IF (
NEW IS DISTINCT FROM OLD AND
NEW.updated_at IS NOT DISTINCT FROM OLD.updated_at
) THEN
NEW.updated_at := current_timestamp;
END IF;
RETURN NEW;
END;
$$ LANGUAGE plpgsql;