Question

我有谷歌在线这个问题，并为我的生活无法弄清楚为什么这一直在抛出错误，任何帮助表示赞赏。

转换nvarchar值'SELECT @orderid时转换失败 = t.orderid FROM（SELECT *，ROW_NUMBER（）OVER（PARTITION BY id ORDER BY creationdatetime DESC）AS row FROM [intranet]。[dbo] .handbook_appendix_data WHERE id ='to data type int。

DECLARE @sql nvarchar(500)
DECLARE @table varchar(40)
SET @table = 'handbook_section_data';
SET @table = 'handbook_appendix_data';

DECLARE @parentid INT
DECLARE @id INT
DECLARE @published INT
DECLARE @orderid INT
SET @parentid = 2
SET @id = -1
SET @published = 1

SET @sql = N'SELECT @orderid = t.orderid FROM 
(SELECT *, ROW_NUMBER() OVER (PARTITION BY id ORDER BY creationdatetime DESC) AS row FROM [intranet].[dbo].'+@table+' WHERE id = '+@id+' AND published = '+@published+') AS t
WHERE t.published = '+@published+' AND t.row = 1';
EXEC SP_EXECUTESQL @sql, N'@orderid INT OUTPUT', @orderid = @orderid OUTPUT --Get the OrderID from ID

PRINT @orderid

Answer 1

您需要将@id和@published整数转换为varchar

 convert(varchar(50),@published)

即

SET @sql = N'SELECT @orderid = t.orderid FROM 
(SELECT *, ROW_NUMBER() OVER (PARTITION BY id ORDER BY creationdatetime DESC) AS row FROM [intranet].[dbo].'+@table+' WHERE id = '+     convert(varchar(50),@id) +' AND published = '+     convert(varchar(50),@published) +') AS t
WHERE t.published = '+convert(varchar(50), @published) +' AND t.row = 1';

更好的解决方案是避免字符串连接，并使用@id传递@published和sp_executesql参数，就像您已使用@orderid一样，或者完全质疑动态SQL的要求？

Answer 2

您需要将整数变量强制转换为字符类型：

 ....
 WHERE id =' + cast(@id as varchar(32)) + ' AND published = ' + cast(@published as varchar(32)) + ') AS t ...

Answer 3

WHERE t.published = '+@published+' AND t.row = 1'

@published是int。 SQL Server已确定+必须介于两个int之间，并且正在尝试将字符串转换为int。

要停止此操作，请将@published强制为字符串 - 然后再添加两个字符串（连接）：

WHERE t.published = '+CONVERT(varchar(10),@published)+' AND t.row = 1'

将nvarchar转换为int

3 个答案: