Let’s insert some records into the “customer_details” table via the “INSERT INTO” command: INSERT INTO customer_details (cust_id, cust_name) Now create one more table named “order_details” with two regular columns and a foreign key: CREATE TABLE order_details(Ĭustomer_id INTEGER REFERENCES customer_details (cust_id) ON DELETE CASCADE,Īn “order_details” table with a foreign key named “customer_id” having the DELETE CASCADE feature enabled has been created. This example will present the stepwise instructions to use the DELETE CASCADE option in Postgres:įirstly, let’s create a “cutomer_details” table with two columns: “cust_id” and “cust_name”: CREATE TABLE customer_details ( This tells Postgres to automatically delete any rows in the referenced table that are related to the row being deleted in the referencing table.Įxample: How Does the DELETE CASCADE Work in Postgres? To use a delete cascade in Postgres, specify the " ON DELETE CASCADE" option while creating/defining a foreign key constraint. This is where Postgres’ DELETE CASCADE feature is extremely useful! Then to keep the database clean and organized, he might also want to delete all of the orders associated with that customer from the "order_details" table. Suppose a user wants to delete a customer from the "customer_details" table. The "order_details" table is linked with the "customer_details" table through a foreign key constraint. So, let’s start!įor instance, consider a database with a "customer_details" and an "order_details" table. This Postgres blog will present a step-by-step guide on how to use the DELETE CASCADE option in Postgres. When a DELETE CASCADE feature is enabled, deleting a record from the referenced/parent table will also delete the referencing records from the child table. In PostgreSQL, a DELETE CASCADE is a powerful feature that is useful when you have multiple tables linked with each other via foreign key constraints.
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