Question

Stack Exchange的居民，

我目前正在尝试创建一个以非常重要的方式重新格式化数据的过程。我得到了关于门票的数据列表（随机月份的摘要）。输入视图始终具有相同的列，但由于我必须将月份显示为列（通常在视图的Monat列中输入值）。 Sooo，经过一些重大的研究，试验和错误以及许多令人头疼的问题，我得让它发挥作用。该过程接受单个票号并“返回”该单个票证上的所有统计信息。

我是这样做的：

遍历每个不同的月份，构建一个CREATE TEMPORARY TABLE语句。
执行该语句，然后取消分配语句
遍历每个票证值，使用INSERT INTO ON DUPLICATE KEY UPDATE语句将其排序到临时表中（我会重新构建，执行和释放每次迭代）
再次迭代每个不同的月份，构建最后一次更新以填充摘要列（我知道，我可以将其合并到第1步，但我尝试将步骤尽可能分开，只是为了让它更容易阅读，我可以根据我的需要进行优化。
选择临时表，以便返回
清理一些松散的头，因为我是一个习惯性的整洁人。

好事：它有效！坏事：它仅适用于一个输入值。每当我将其更改为另一个票号时，这将需要不同月份的列，它会失败，并显示“错误代码1054，字段列表中的未知列”，指的是当前查询不应具有的旧列（月）。我可以根据需要多次运行该过程，只要临时表的列相同即可。每当我删除并重新创建过程或创建新连接时，此行为都会重置。

显然，我忘了在整个过程中的某个地方做一个清理步骤，而且我对SQL一般都是新手，特别是MySQL可能甚至不知道要找它：（。

非常感谢帮助，谢谢，佛瑞德

DELIMITER //
CREATE PROCEDURE proc_get_relevant_tickets(bID VARCHAR(10))
DETERMINISTIC
READS SQL DATA
BEGIN
# Declare storage vairables for withdrawing data from view
DECLARE ID, FiID, ZVB, ZNVB, ZGes, WVB, WNVB, WGes INTEGER;
DECLARE Mon VARCHAR(50);
DECLARE RowVerb, RowNVerb, RowGes, Counter INTEGER;
DECLARE verbucht, nichtverbucht, gesamt VARCHAR(50);
DECLARE currentticket INTEGER;
DECLARE statezges, statewges LONGTEXT;

# Declare runtime stuff
DECLARE done INT DEFAULT FALSE;
DECLARE declaration LONGTEXT;
DECLARE temptext VARCHAR(50);
DECLARE Months CURSOR FOR SELECT DISTINCT Monat FROM view_list_of_tickets t WHERE bID = t.ID;
DECLARE `Values` CURSOR FOR SELECT * FROM view_list_of_tickets t WHERE bID = t.ID;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

# Clean up in case something interrupted last execution
DROP TEMPORARY TABLE IF EXISTS temp_storage_5437485;

# If there are any entries to work upon
IF (SELECT COUNT(t.ID) FROM view_list_of_tickets t WHERE bID = t.ID > 0)
THEN
    # Create temporary table to put the values into
    SET declaration = 'CREATE TEMPORARY TABLE `temp_storage_5437485` (ID INTEGER PRIMARY KEY, TicketNr INTEGER, Category VARCHAR(50), ';

    SET done = FALSE;
    OPEN Months;
    read_loop: LOOP
        FETCH Months INTO temptext;
        IF done THEN
            LEAVE read_loop;
        END IF;
        SET declaration = CONCAT(declaration, '`', temptext, ' Zeit` INTEGER DEFAULT 0, ');
        SET declaration = CONCAT(declaration, '`', temptext, ' Wert` INTEGER DEFAULT 0, ');
    END LOOP;
    CLOSE Months;

    SET declaration = CONCAT(declaration, '`Gesamt Zeit` INTEGER, `Gesamt Wert` INTEGER);');
    SELECT declaration INTO @declaration;
    PREPARE stmt FROM @declaration;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;
    # End of creating the storage container

    # Cycle through values and input into temporary table
    SET done = FALSE;
    SET verbucht = 'Verbucht';
    SET nichtverbucht = 'Nicht Verbucht';
    SET gesamt = 'Gesamt';
    SET currentticket = 0;
    SET Counter = 0;
    SET RowVerb = 1;
    SET RowNVerb = 2;
    SET RowGes = 3;
    OPEN `Values`;
    read_values: LOOP
        FETCH `Values` INTO ID, FiID, ZVB, ZNVB, ZGes, WVB, WNVB, WGes, Mon;
        IF done THEN
            LEAVE read_values;
        END IF;

        # If a new ticket has been arrived at, increment the counters
        IF currentticket > 0 AND ID <> currentticket THEN
            SET currentticket = ID;
            SET Counter = Counter + 1;
            SET RowVerb = RowVerb + 3;
            SET RowNVerb = RowNVerb + 3;
            SET RowGes = RowGes + 3;
        END IF;

        IF currentticket = 0 AND ID <> currentticket THEN
            SET currentticket = ID;
        END IF;

        # Insert first (Verbucht) row
        SET declaration = CONCAT('INSERT INTO `temp_storage_5437485` (`ID`, `TicketNr`, `', Mon, ' Zeit`, `', Mon, ' Wert`) VALUES (');
        SET declaration = CONCAT(declaration, RowVerb, ', ', ID, ', ', ZVB, ', ', WVB, ') ON DUPLICATE KEY UPDATE ');
        SET declaration = CONCAT(declaration, '`', Mon, ' Zeit`=', ZVB, ', `', Mon, ' Wert`=', WVB, ';');
        SELECT declaration INTO @declaration;
        PREPARE stmt FROM @declaration;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;

        # Insert second (Nicht Verbucht) row
        SET declaration = CONCAT('INSERT INTO `temp_storage_5437485` (`ID`, `TicketNr`, `', Mon, ' Zeit`, `', Mon, ' Wert`) VALUES (');
        SET declaration = CONCAT(declaration, RowNVerb, ', ', ID, ', ', ZNVB, ', ', WNVB, ') ON DUPLICATE KEY UPDATE ');
        SET declaration = CONCAT(declaration, '`', Mon, ' Zeit`=', ZNVB, ', `', Mon, ' Wert`=', WNVB, ';');
        SELECT declaration INTO @declaration;
        PREPARE stmt FROM @declaration;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;

        # Insert third (Gesamt) row
        SET declaration = CONCAT('INSERT INTO `temp_storage_5437485` (`ID`, `TicketNr`, `', Mon, ' Zeit`, `', Mon, ' Wert`) VALUES (');
        SET declaration = CONCAT(declaration, RowGes, ', ', ID, ', ', ZGes, ', ', WGes, ') ON DUPLICATE KEY UPDATE ');
        SET declaration = CONCAT(declaration, '`', Mon, ' Zeit`=', ZGes, ', `', Mon, ' Wert`=', WGes, ';');
        SELECT declaration INTO @declaration;
        PREPARE stmt FROM @declaration;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;

        UPDATE temp_storage_5437485 SET Category = verbucht WHERE temp_storage_5437485.ID = RowVerb LIMIT 5;
        UPDATE temp_storage_5437485 SET Category = nichtverbucht WHERE temp_storage_5437485.ID = RowNVerb LIMIT 5;
        UPDATE temp_storage_5437485 SET Category = gesamt WHERE temp_storage_5437485.ID = RowGes LIMIT 5;
    END LOOP;
    CLOSE `Values`;
    # End of cycling for values input

    # Being calculating the total values
    SET declaration = 'UPDATE temp_storage_5437485 SET `Gesamt Zeit` = (';
    SET statezges = '';
    SET statewges = '';

    SET done = FALSE;
    OPEN Months;
    read_loop: LOOP
        FETCH Months INTO temptext;
        IF done THEN
            LEAVE read_loop;
        END IF;

        # If not the first entry, add more
        IF statezges <> '' THEN
            SET statezges = CONCAT(statezges, ' + ');
        END IF;
        IF statewges <> '' THEN
            SET statewges = CONCAT(statewges, ' + ');
        END IF;

        # Add column name
        SET statezges = CONCAT(statezges, 'temp_storage_5437485.`', temptext, ' Zeit`');
        SET statewges = CONCAT(statewges, 'temp_storage_5437485.`', temptext, ' Wert`');
    END LOOP;
    CLOSE Months;

    SET declaration = CONCAT(declaration, statezges, '), `Gesamt Wert` = (', statewges, ') LIMIT 100000');
    SELECT declaration INTO @declaration;
    PREPARE stmt FROM @declaration;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;
    # End calculating the total values

    SELECT * FROM temp_storage_5437485;
    DROP TEMPORARY TABLE IF EXISTS temp_storage_5437485;
ELSE
    SELECT 'is null';
END IF;

DROP TEMPORARY TABLE IF EXISTS temp_storage_5437485;
END //

DELIMITER ;

如果第二次调用创建其他列，则过程失败

0 个答案: