Question

我坚持这个。

基本上我选择VARCHAR类型的列中的值。但是当我选择这些值时，我需要将CAST / CONVERT全部转换为整数。

问题出现在列I中，从某些值中选择值包含字符串字符，因此当我运行查询时，出现错误，说明以下内容：

Msg 245，Level 16，State 1，Line 1转换时转换失败 varchar值＆＃39; NA＆＃39;数据类型int。

这是我的select声明

SELECT DISTINCT 
  DP.Owner_Faculty_Full_Desc AS 'Faculty'
, DP.Programme_Full_Desc AS 'Programme'
, LEFT(FA.Teaching_Start_Date_Key, 4) AS 'Year' 
, SD.Last_Secondary_School_Name AS 'School'
, CAST(CASE WHEN SD.Last_Secondary_School_Decile_Code = 'UN' THEN '0' ELSE SD.Last_Secondary_School_Decile_Code END AS INT) AS 'Decile'
, COUNT(FA.Student_Demographics_Key) AS 'Total Applicants 2014'
, SUM(SE.Total_EFTS) AS 'Total EFTS'

我需要将SD.Last_Secondary_School_Code列中的所有值作为整数拉入。

Answer 1

我希望知道这个新的（至少对我:) :)语法很好：

SELECT 
 id, 
 value, 
 IIF(TRY_PARSE(value AS int) IS not NULL, value, 0) AS Result 
FROM 
  table1

参考：https://msdn.microsoft.com/en-us/library/hh213126(v=sql.110).aspx

Answer 2

如果我理解正确，只需使用case：

(CASE WHEN SD.Last_Secondary_School_Decile_Code = 'UN' THEN 0
      WHEN SD.Last_Secondary_School_Decile_Code not like '%[^0-9]%'
      THEN CAST(SD.Last_Secondary_School_Decile_Code AS INT)
 END) AS Decile

如何将列CAST / CONVERT到包含字符串值的整数

2 个答案: