在SQL Server 2008中如何在选择中使用反向和拆分？

Question

我发现以下查询对于我正在处理的应用程序非常有用。 但是，我想替换表中select的值。

WITH data AS
(
    select Value, REVERSE(Value) AS ReverseValue from (values
        ('texttext/21/812/21a'), ('texttext/6/163/38a'), ('texttext/53/7a/a2'), ('text/t/e/xt/53/7a/a2')
    )t(Value)
), split AS
(
    select 
        Value, ReverseValue, 
        reverse(substring(ReverseValue, 1, P1.Pos - 1)) AS Forth,
        reverse(substring(ReverseValue, P1.Pos + 1, P2.Pos - P1.Pos - 1)) AS Third,
        reverse(substring(ReverseValue, P2.Pos + 1, P3.Pos - P2.Pos - 1)) AS Second,
        reverse(substring(ReverseValue, p3.Pos + 1, len(ReverseValue))) AS First
    from data       
        cross apply (select (charindex('/', ReverseValue))) as P1(Pos)
        cross apply (select (charindex('/', ReverseValue, P1.Pos+1))) as P2(Pos)
        cross apply (select (charindex('/', ReverseValue, P2.Pos+1))) as P3(Pos)
)
select Value, First + '-' + Forth + Third + Second AS NewValue from split

因此，我想要的不是(values ('texttext/21/812/21a') (...)而是类似(select myfield from myutable)东西。

Answer 1

只需替换第一个CTE中的值即可：

WITH data AS (
    select myfield, REVERSE(myfield) AS ReverseValue
    from mytable
   ),
   . . .