Question

我正在创建一个插入表的存储过程。以下将提供我的表格列

Create Table Item 
(
    ID char(20),
    Name varchar(max) NOT NULL,
    Brand char(10) NOT NULL,
    Category char(10) NOT NULL,
    Unit_Of_Measure char(5) NOT NULL,
    Price decimal(18,2) NOT NULL,
    [Image] image NOT NULL,
    Active bit NOT NULL Default('True')

    Constraint PK_Item Primary Key (ID),
    Constraint FK_Item_Brands Foreign Key (Brand) References Brands(ID),
    Constraint FK_Item_Item_Category Foreign Key (Category) References Item_Category(ID),
    Constraint FK_Item_Unit_Of_Measure Foreign Key (Unit_Of_Measure) References Unit_Of_Measure(ID)
);
go

表插件工作正常。在我们走得更远之前，我需要展示我得到的错误。

Msg 50000，Level 16，State 2，Procedure stpItem，Line 66
操作数类型冲突：图像与nvarchar
不兼容

当我执行下面的命令时，会出现上述错误，之后您将看到存储过程

exec stpItem '','GG','2','2','2',123.12, null, 'true', 'false'

存储过程代码：

Create Proc stpItem
    @ID varchar(max),
    @Name varchar(max),
    @Brand varchar(max),
    @Category varchar(max),
    @UOM varchar(max),
    @Price decimal,
    @Image Image,
    @Active bit,
    @Update bit
As
   Set Transaction Isolation Level Serializable
   Begin Transaction
   Begin Try

-- If it is an insertion
IF @Update = 'False' 
Begin

Declare @Pre char(1),
        @Len int,
        @Next int,
        @Start int,
        @SetKey varchar(max);

Set @SetKey = '';
Select @Pre = Prefix, @Len = [Length], @Next = [Next] From Key_Generation Where Table_Name = 'Item';
Set @Start = 1;
Set @Len = @Len - 1;
While @Start < @Len
Begin
set @SetKey = @SetKey + '0'
set @Start = @Start + 1;
End

Exec('Declare @LID char(20); Set @LID =  (select ''' + @Pre + ''' + right(''' + @SetKey + ''' + cast(' + @Next + ' as varchar(' + @Len + ')), ' + @Len + '));' +
'Insert into Item Values (@LID,''' + @Name + ''',''' + @Brand + ''',''' + @Category + ''',''' + @UOM + ''',' + @Price + ',' + @Image + ' ,' + @Active + ');' + 
'Update Key_Generation Set [Next] = [Next] + 1 Where Table_Name = ''Item'';');

End
Else
Begin

   Update Item 
   Set Name = @Name, 
       [Brand] = @Brand, 
       [Category] = @Category, 
       [Unit_Of_Measure] = @UOM, 
       Price = @Price, 
       [Image] = @Image, 
       Active = @Active 
   Where ID = @ID;
End

Commit Transaction;
End Try
Begin Catch
    Rollback Transaction;

    DECLARE @ErrorMessage NVARCHAR(4000);
    DECLARE @ErrorSeverity INT;
    DECLARE @ErrorState INT;

    SELECT 
        @ErrorMessage = ERROR_MESSAGE(),
        @ErrorSeverity = ERROR_SEVERITY(),
        @ErrorState = ERROR_STATE();

    -- Use RAISERROR inside the CATCH block to return error
    -- information about the original error that caused
    -- execution to jump to the CATCH block.
    RAISERROR (@ErrorMessage, -- Message text.
               @ErrorSeverity, -- Severity.
               @ErrorState -- State.
               );
End Catch

有人能告诉我为什么会收到此错误，以及如何解决此问题？

Answer 1

您不是在这里将非varchar变量转换为varchar：

 @Price + ',' + @Image + ' ,' + @Active + ');'

尝试：

 cast(@price as varchar(max)) + ',' + cast(@image as varchar(max)) + ...

Answer 2

cast(cast(@Image as binary) as nvarchar(max));

我使用nvarchar变量从外部转换它然后在og执行命令

中使用它

Declare @txtImage nvarchar(max);
if @Image IS NULL
Begin Set @txtImage = 'NULL'; END
Else
Begin Set @txtImage = cast(cast(@Image as binary) as nvarchar(max)); END

为什么我在SQL Server中出现此错误？如何解决？

2 个答案: