1create table lifetime_usages (
2    id serial primary key,
3    user_id integer not null,
4    model_id integer not null references models (id) on delete cascade,
5    input_tokens bigint not null default 0,
6    output_tokens bigint not null default 0
7);
8
9create unique index uix_lifetime_usages_on_user_id_model_id on lifetime_usages (user_id, model_id);