[Rails] How to properly update postgresql array?

Question

PostgreSQL

There is an array field in the postgresql table:
t.string :favorits, array: true, default: []
From time to time I need to add and remove elements from this field:

@user.favorits.delete_at("has_value")
@user.favorits.unshift("new_value")
@user.save

However, all these changes are not saved. What am I doing wrong?

Answer 1

...
@user.favorits_will_change!
@user.save

Answer 2

Maybe try @user.save!?