

@dispatch(Field, sa.Column)
def compute_up(t, s, **kwargs):
    assert (len(s.foreign_keys) == 1), 'exactly one foreign key allowed'
    key_col = first(t.foreign_keys).column
    return sa.select([key_col.table.c[t._name]]).where((s == key_col))

dataset/ETHPy150Open blaze/blaze/blaze/compute/sql.py compute_up/VarMisuse@43/58 `s`->`t`