转换失败

Question

我有一个存储过程在一个图案中插入数据，

DECLARE @I INT = 1 
DECLARE @ID INT = 0 
DECLARE @PackID VARCHAR(50) 

SELECT @PackID = MAX(PackID) 
FROM tblPacks 
WHERE PackID LIKE 'PK%' 

IF(@String = 'Packs') 
BEGIN 
    WHILE @I <= @Count 
    BEGIN 
     IF @PackID IS NULL 
     BEGIN 
      SET @I = @I + 1 
      SET @ID = @ID + 1 

      INSERT INTO tblPacks (T_ID, BatchNumber, PackID, Status, BlistersCount) 
      VALUES (@T_ID, @BatchNumber, 
        'PK'+ CAST(@ID as VARCHAR(50)), 0, 
        (SELECT NumberOfBlistersInEachPack 
        FROM tblPackDetails 
        WHERE T_ID = @T_ID AND BatchNumber = @BatchNumber)) 
     END   
     ELSE 
     BEGIN 
      SET @I = @I + 1 
      error :- SELECT @ID = (SELECT MAX(PackID) FROM tblPacks) 
      SET @ID = @ID + 1 

      INSERT INTO tblPacks (T_ID, BatchNumber, PackID, Status, BlistersCount) 
      VALUES (@T_ID, @BatchNumber, 
        'PK'+ CAST(@ID as VARCHAR(50)), 0, 
        (SELECT NumberOfBlistersInEachPack 
         FROM tblPackDetails 
         WHERE T_ID = @T_ID AND BatchNumber = @BatchNumber)) 
      END 
     END 
    END 
END 

它是否显示错误：

Conversion failed when converting the varchar value 'PK3' to data type int.

如果packid为null，那么它应该是'PK1'，如果它有一些数据，那么它会取最大值，然后它应该增加'1'。我应该在哪里修改我的代码以摆脱此错误？

Answer 1

尝试把下面的语句进行插入查询

('PK'+CAST(@ID as VARCHAR(50))) 

这里我们首先需要转换成整数类型为varchar，然后拼接它。

Answer 2

试试这个，一旦它可以帮助你。 首先将整型变量转换为字符串，然后与字符串变量连接。 查询中的INT加入这个块，并享受..

'PK'+ CAST(@ID as VARCHAR(50))

DECLARE @I INT=1 
     DECLARE @ID INT=0 
     DECLARE @PackID VARCHAR(50) 


    SELECT @PackID=MAX(PackID) FROM tblPacks WHERE PackID LIKE 'PK%' 

    IF(@String='Packs') 
    BEGIN 
    WHILE @I<=@Count 
    BEGIN 
    IF @PackID IS NULL 
    BEGIN 
    SET @I=@I+1 
    SET @ID=@ID+1 
    INSERT INTO tblPacks (T_ID,BatchNumber,PackID,Status,BlistersCount) 
    VALUES (
     @T_ID,@BatchNumber, 
    'PK'+ CAST(@ID as VARCHAR(50)) ,0,(SELECT NumberOfBlistersInEachPack FROM tblPackDetails WHERE T_ID=@T_ID AND BatchNumber=@BatchNumber)) 

    END 

    ELSE 
    BEGIN 
    SET @I=@I+1 
    SELECT @ID=(SELECT MAX(PackID) FROM tblPacks) 
    SET @ID=@ID+1 
    INSERT INTO tblPacks (T_ID,BatchNumber,PackID,Status,BlistersCount) 
    VALUES (
     @T_ID,@BatchNumber, 
     'PK'+ CAST(@ID as VARCHAR(50)) ,0,(SELECT NumberOfBlistersInEachPack FROM tblPackDetails WHERE T_ID=@T_ID AND BatchNumber=@BatchNumber)) 
    END 
    END 
    END 
END 

Answer 3

你也可以你一些字符串函数来转换为varchar，例如：

DECLARE @ID INT =100 
SELECT 'PK'+LTRIM(@ID) 

Answer 4

请注明线＃在其中你得到错误。这只是一个转换错误。请指定表格定义。参考下面的查询。我改变了连接部分。如果错误仍然存​​在，请分享表格定义和错误的行号＃。另请参阅tblPacks中的PackID列的数据类型是什么？ PackID是非数字，您试图将该值分配给@ID，该值声明为INT。这就是问题。我强烈建议使用其他值而不是采用字符串的最大值。我又修改了查询以从PackID

DECLARE @I INT = 1 
DECLARE @ID INT = 0 
DECLARE @MaxPackID VARCHAR(50) 
DECLARE @PackID VARCHAR(50) 


SELECT @PackID = MAX(PackID) 
FROM tblPacks 
WHERE PackID LIKE 'PK%' 

IF(@String = 'Packs') 
BEGIN 
    WHILE @I <= @Count 
    BEGIN 
     IF @PackID IS NULL 
     BEGIN 
      SET @I = @I + 1 
      SET @ID = @ID + 1 

      INSERT INTO tblPacks (T_ID, BatchNumber, PackID, Status, BlistersCount) 
      VALUES (@T_ID, @BatchNumber, 
        'PK' + CAST(@ID AS VARCHAR(50)), 0, 
        (SELECT NumberOfBlistersInEachPack 
        FROM tblPackDetails 
        WHERE T_ID = @T_ID AND BatchNumber = @BatchNumber)) 
     END   
     ELSE 
     BEGIN 
      SET @I = @I + 1 
      SELECT @MaxPackID = MAX(SUBSTRING(PackID,PATINDEX('%[0-9]%',PackID),LEN(PackID))) FROM tblPacks 
      SELECT @ID = @MaxPackID 
      SET @ID = @ID + 1 

      INSERT INTO tblPacks (T_ID, BatchNumber, PackID, Status, BlistersCount) 
      VALUES (@T_ID, @BatchNumber, 
        'PK' + CAST(@ID AS VARCHAR(50)), 0, 
        (SELECT NumberOfBlistersInEachPack 
         FROM tblPackDetails 
         WHERE T_ID = @T_ID AND BatchNumber = @BatchNumber)) 
      END 
     END 
    END 
END