[Solved] sql update multiple rows with multi join subselect

Question

This idea is fundamentally doomed to fail. You’re trying to get the SQL server to link a graduation class to a user by itself, despite the SQL server not having information on which graduation class should be linked to the user. Unless you have some data somewhere (in user, in graduation_class, in some other table) that links a user_id to the graduation term, class, or year (or someone manually telling SQL which data match up), SQL can’t magically do that job for you.

Accepted Answer

This idea is fundamentally doomed to fail. You’re trying to get the SQL server to link a graduation class to a user by itself, despite the SQL server not having information on which graduation class should be linked to the user. Unless you have some data somewhere (in user, in graduation_class, in some other table) that links a user_id to the graduation term, class, or year (or someone manually telling SQL which data match up), SQL can’t magically do that job for you.