How to fix Referential Integrity Violation Error in CakePHP?

Question

PostgreSQL

There are two tables: users (id, ....) and logs (id, user_id, ...).
Logs has a referential integrity constraint:

FOREIGN KEY (user_id) REFERENCES users(id) ON UPDATE CASCADE ON DELETE RESTRICT

Inside the transaction, I create an entry in users, then in logs, putting the user_id of the "freshly created" user there. In this case, a foreign key violation error occurs, with a message that there is no entry in users for the specified user_id, although there is an entry when fetching with find().
Please tell me how can this be fixed?