pypyodbc.py 文件源码

def prepare(self, query_string):
        """prepare a query"""

        #self._free_results(FREE_STATEMENT)
        if not self.connection:
            self.close()

        if type(query_string) == unicode:
            c_query_string = wchar_pointer(UCS_buf(query_string))
            ret = ODBC_API.SQLPrepareW(self.stmt_h, c_query_string, len(query_string))
        else:
            c_query_string = ctypes.c_char_p(query_string)
            ret = ODBC_API.SQLPrepare(self.stmt_h, c_query_string, len(query_string))
        if ret != SQL_SUCCESS:
            check_success(self, ret)


        self._PARAM_SQL_TYPE_LIST = [] 

        if self.connection.support_SQLDescribeParam:
            # SQLServer's SQLDescribeParam only supports DML SQL, so avoid the SELECT statement
            if True:# 'SELECT' not in query_string.upper():
                #self._free_results(NO_FREE_STATEMENT)
                NumParams = c_short()
                ret = ODBC_API.SQLNumParams(self.stmt_h, ADDR(NumParams))
                if ret != SQL_SUCCESS:
                    check_success(self, ret)

                for col_num in range(NumParams.value):
                    ParameterNumber = ctypes.c_ushort(col_num + 1)
                    DataType = c_short()
                    ParameterSize = ctypes.c_size_t()
                    DecimalDigits = c_short()
                    Nullable = c_short()
                    ret = ODBC_API.SQLDescribeParam(
                        self.stmt_h,
                        ParameterNumber,
                        ADDR(DataType),
                        ADDR(ParameterSize),
                        ADDR(DecimalDigits),
                        ADDR(Nullable),
                    )
                    if ret != SQL_SUCCESS:
                        try:
                            check_success(self, ret)
                        except DatabaseError:
                            if sys.exc_info()[1].value[0] == '07009':
                                self._PARAM_SQL_TYPE_LIST = [] 
                                break
                            else:
                                raise sys.exc_info()[1]
                        except:
                            raise sys.exc_info()[1]

                    self._PARAM_SQL_TYPE_LIST.append((DataType.value,DecimalDigits.value))

        self.statement = query_string