Question

I have a query with a subquery that returns multiple rows.

I have a table with lists and a table with users. I created a many-to-many table between these two tables, called list_user.

LIST
id INTEGER
list_name TEXT
list_description TEXT

USER
id INTEGER
user_name TEXT

LIST_USER
id INTEGER
list_id INTEGER
user_id INTEGER

My query with subquery

SELECT * FROM user WHERE id = (SELECT user_id FROM list_user WHERE list_id = 0);

The subquery works (and I use it in code so the 0 is actually a variable) and it returns multiple rows. But the upper query only returns one row, which is pretty logical; I check if the id equals something and it only checks against the first row of the subquery.

How do I change my statement so I get multiple rows in the upper query?

Answer 1

I’m surprised the = works in SQLite. It would return an error in most databases. In any case, you want the in statement:

SELECT *
FROM list
WHERE id in (SELECT user_id FROM list_user WHERE list_id = 0);