SQLite database schema for a notes app with fulltext search and maintenance triggers

app_with_fts_triggers.sql

create table if not exists note (
  id integer not null primary key autoincrement,
  created_at timestamp not null default current_timestamp,
  modified_at timestamp not null default current_timestamp,
  starred_at timestamp,
  title varchar(1024) not null,
  content text not null default ''
);

create table if not exists note_tag (
  note_id integer not null,
  tag varchar(512) not null,
  tagged_at timestamp not null default current_timestamp,
  constraint fk_note_id foreign key(note_id) references note(id) on delete cascade,
  constraint uk_note_id_tag unique(note_id, tag)
);

create table if not exists note_link (
  from_note_id integer not null,
  to_note_id integer not null check (from_note_id < to_note_id),
  linked_at timestamp not null default current_timestamp,
  constraint fk_from_note_id foreign key(from_note_id) references note(id) on delete cascade,
  constraint fk_to_note_id foreign key(to_note_id) references note(id) on delete cascade,
  constraint uk_note_link unique(from_note_id, to_note_id)
);

create virtual table if not exists note_search using fts5(
  title,
  content,
  tokenize = 'porter unicode61 remove_diacritics 1',
  content = 'note',
  content_rowid = 'id',
  columnsize = 0
);

create trigger if not exists note_search_ins after insert on note begin
  insert into note_search (rowid, title, content)
  values (new.id, new.title, new.content);
end;

create trigger if not exists note_search_del after delete on note begin
  insert into note_search (note_search, rowid, title, content)
  values ('delete', old.id, old.title, old.content);
end;

create trigger if not exists note_search_upd after update on note begin
  insert into note_search (note_search, rowid, title, content)
  values ('delete', old.id, old.title, old.content);

  insert into note_search (rowid, title, content)
  values (new.id, new.title, new.content);
end;

create trigger if not exists index_note_delete before delete on note when old.id = 1 begin
  select raise(fail, 'cannot delete index note');
end;

create trigger if not exists index_note_update before update on note when old.id = 1 and new.id <> 1 begin
  select raise(fail, 'cannot change index note ID');
end