If i use keycloak, do I need user table for my backend?

Let say I login via keycloak js inside react and able to get the user detail like id, email etc…

should i use that id to create one more user record inside my user table? or I dont need a user table, instead i use that id as a fk for other user-related data LIke:

Pattern 1:

Post:
id,
keycloak_user_id,
body.

Pattern 2:
User:
id [use keycloak user id]

Post:
id,
USER.id
body