create table sources(
    name text not null,
    primary key (name)
) strict;
create table actions(
    source text not null,
    name text not null,
    argv blob not null,
    primary key (source, name),
    foreign key (source) references sources (name) on delete cascade
) strict;
create table items(
    source text not null,
    id text not null,
    created int not null default (unixepoch()),
    active int not null,
    title text,
    author text,
    body text,
    link text,
    time int,
    action blob,
    primary key (source, id),
    foreign key (source) references sources (name) on delete cascade
) strict;