Delete rows from two tables in one query

Question

I have two tables: orders and orders_items. Both sharing the field orderID.

I want to delete all rows from both tables where orderID=500, but I need to do this in only o

Answer 1

Here's a simply solution if you're using MySQL/PgSQL...

DELETE t1, t2 FROM table1 AS t1 
LEFT JOIN table2 AS t2 USING( orderID ) 
WHERE t1.orderID = 500;

Guaranteed to work like a charm!

Make sure to replace table1 and table2 with appropriate table names in your case.

I've used plenty of this query in my custom designed CMS - wherever I've wanted to avoid two distinct atomic queries. This is as good as a cascading delete and the query can be expanded to span over as many tables as you want.

Here's another example involving 3 tables:

DELETE t1, t2, t3 FROM table1 AS t1 
LEFT JOIN table2 AS t2 USING( orderID ) 
LEFT JOIN table3 AS t3 USING( orderID ) 
WHERE t1.orderID = 500;

Cheers, m^e