'Get table constraints.'

def create_table_constraints(self, table):

    constraint_string = super(MySQLDDLCompiler, self).create_table_constraints(table)
    is_innodb = (('engine' in table.dialect_options[self.dialect.name]) and (table.dialect_options[self.dialect.name]['engine'].lower() == 'innodb'))
    auto_inc_column = table._autoincrement_column
    if (is_innodb and (auto_inc_column is not None) and (auto_inc_column is not list(table.primary_key)[0])):
        if constraint_string:
            constraint_string += ',    \n DCTB '
        constraint_string += ('KEY    %s    (%s)' % (self.preparer.quote(('idx_autoinc_%s' % auto_inc_column.name)), self.preparer.format_column(auto_inc_column)))
    return constraint_string
