def get_select_precolumns(self, select):
        if select._distinct or select._limit is not None:
            s = select._distinct and "DISTINCT " or ""

            # ODBC drivers and possibly others
            # don't support bind params in the SELECT clause on SQL Server.
            # so have to use literal here.
            if select._limit is not None:
                if not select._offset:
                    s += "TOP %d " % select._limit
            return s
        return compiler.SQLCompiler.get_select_precolumns(self, select)
MS-SQL puts TOP, its version of LIMIT, here
dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/dialects/mssql/base.py/MSSQLCompiler.get_select_precolumns