There is also a card on updating multiple columns with multiple joins in PostgreSQL. Here is what my update logic looks like right now. In PostgreSQL the syntax is a little unfamiliar: UPDATE employees But I want to subsequently UPDATE this table whenever either the customer or payment tables get updated, and this is where Im lost in the woods. LEFT JOIN departments ON partment_id = departments.id Use the UPDATE Statement Only to Update the Table in PostgreSQL. In MySQL you can do it like this: UPDATE employees Since the department's name lives in another table, you need to JOIN both tables during the UPDATE. Now you need to backfill existing Employee records with the new department_name. You add the column like this: ALTER TABLE employees ADD COLUMN department_name TEXT | email |-|-+īecause of performance reason you decide to cache the department's name into a new column Employee#department_name: +-+ Let's say you have a database schema where an Employee belongs_to :department: +-+
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