create table if not exists frequencies (
  id integer primary key autoincrement,
  description text not null default ''
);

insert into frequencies (id, description) values
  (1, 'daily'),
  (2, 'weekly'),
  (3, 'fortnightly'),
  (4, 'monthly'),
  (5, 'seasonally'),
  (6, 'semiannually'),
  (7, 'yearly')
  on conflict (id) do update set description=excluded.description;


create table if not exists tasks (
  id integer primary key autoincrement,
  description text not null default '',
  frequency_id integer not null references frequencies(id) on delete cascade
);

create table if not exists completions (
  id integer primary key autoincrement,
  task_id integer not null references tasks(id) on delete cascade,
  datestamp text not null
);