def _alter_add_positive_check(self, klass, field, name, params, sqls):
        super(klass, self)._alter_add_column_mods(field, name, params, sqls)
        if isinstance(field, (models.PositiveSmallIntegerField, models.PositiveIntegerField)):
            uniq_hash = abs(hash(tuple(params.values())))
            d = dict(
                     constraint = "CK_%s_PSTV_%s" % (name, hex(uniq_hash)[2:]),
                     check = "%s >= 0" % self.quote_name(name))
            sqls.append((self.add_check_constraint_fragment % d, []))


# Single-level flattening of lists
Update the layout configuration using layout operations.
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/South-1.0.2/south/db/generic.py/DatabaseOperations._alter_add_positive_check--crossover with--dataset/ETHPy150Open ContinuumIO/ashiba/enaml/enaml/widgets/dock_area.py/DockArea.update_layout