Sql Server --去掉非数字字符

Question

我有一张桌子

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[TestAB](
    [A] [int] IDENTITY(1,1) NOT NULL,
    [B] [nvarchar](10) NULL,
 CONSTRAINT [PK_TestAB] PRIMARY KEY CLUSTERED 
(
    [A] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

值类似于

INSERT INTO [TestAB]([B]) 
    VALUES('A1');

INSERT INTO [TestAB]([B]) 
    VALUES('A2');

INSERT INTO [TestAB]([B]) 
    VALUES('A5');

INSERT INTO [TestAB]([B]) 
    VALUES('A4');

INSERT INTO [TestAB]([B]) 
    VALUES('AA5');

INSERT INTO [TestAB]([B]) 
    VALUES('A9');

INSERT INTO [TestAB]([B]) 
    VALUES('C7');

INSERT INTO [TestAB]([B]) 
    VALUES('D8');

INSERT INTO [TestAB]([B]) 
    VALUES('D-9');

INSERT INTO [TestAB]([B]) 
    VALUES('R$10');

​

​

​

​

我想去掉非数字字符并将nvarchar数字转换为整数，然后比较它们在哪里是!=

Answer 1

Select A,B,Case when A<>B then 0 else 1 end
from
(
select
A,
Cast(
Left(SubString(B, PatIndex('%[0-9.-]%', B), 100),
     PatIndex('%[^0-9.-]%', SubString(B, PatIndex('%[0-9.-]%', B), 100)+'_' )-1)
as int) as B
from TestAB
) aa 
where A<>B

SQL-Fiddle

Answer 2

您没有具体指定应该返回哪些行，但我认为这可以满足您的需要：

select A, B
from dbo.TestAB
where cast(replace(B, replace(B, cast(A as nvarchar(10)), ''), '') as int) <> A

Answer 3

这是Pinal Dave's UDF的recursive CTE版本，尽管我们去掉了除数字以外的所有内容：

;with digitsOnly as (
    select A, B, B as DigitB, patindex(N'%[^0-9]%', B) as IncorrectCharLoc
    from TestAB
    union all
    select A, B, cast(stuff(DigitB, IncorrectCharLoc, 1, N'') as nvarchar(10))
        , patindex(N'%[^0-9]%', stuff(DigitB, IncorrectCharLoc, 1, N''))
    from digitsOnly
    where IncorrectCharLoc > 0
)
select A, B, DigitB
from digitsOnly
where IncorrectCharLoc = 0 -- Get last iteration
    and cast(A as nvarchar(10)) <> DigitB -- Final compare
order by A
option (maxrecursion 0)

/*
    A           B          DigitB
    ----------- ---------- ----------
    3           A5         5
    6           A9         9
*/