def _samp_compute_up(t, s, **kwargs):
    if t.n is not None:
        limit = t.n
    else:
        limit = sa.select([safuncs.count() - t.frac],
                          from_obj=s.alias()).as_scalar()
    return s.order_by(safuncs.random()).limit(limit)
dataset/ETHPy150Open blaze/blaze/blaze/compute/sql.py/_samp_compute_up/operator `*` -> `-`