Взяв замечательную функцию от Алана Бурштейна под названием PatExclude8K , которую я включаю сюда
CREATE FUNCTION dbo.PatExclude8K
(
@String VARCHAR(8000),
@Pattern VARCHAR(50)
)
/*******************************************************************************
Purpose:
Given a string (@String) and a pattern (@Pattern) of characters to remove,
remove the patterned characters from the string.
Usage:
--===== Basic Syntax Example
SELECT CleanedString
FROM dbo.PatExclude8K(@String,@Pattern);
--===== Remove all but Alpha characters
SELECT CleanedString
FROM dbo.SomeTable st
CROSS APPLY dbo.PatExclude8K(st.SomeString,'%[^A-Za-z]%');
--===== Remove all but Numeric digits
SELECT CleanedString
FROM dbo.SomeTable st
CROSS APPLY dbo.PatExclude8K(st.SomeString,'%[^0-9]%');
Programmer Notes:
1. @Pattern is not case sensitive (the function can be easily modified to make it so)
2. There is no need to include the "%" before and/or after your pattern since since we
are evaluating each character individually
Revision History:
Rev 00 - 10/27/2014 Initial Development - Alan Burstein
Rev 01 - 10/29/2014 Mar 2007 - Alan Burstein
- Redesigned based on the dbo.STRIP_NUM_EE by Eirikur Eiriksson
(see: http://www.sqlservercentral.com/Forums/Topic1585850-391-2.aspx)
- change how the cte tally table is created
- put the include/exclude logic in a CASE statement instead of a WHERE clause
- Added Latin1_General_BIN Colation
- Add code to use the pattern as a parameter.
Rev 02 - 11/6/2014
- Added final performane enhancement (more cudo's to Eirikur Eiriksson)
- Put 0 = PATINDEX filter logic into the WHERE clause
Rev 03 - 5/16/2015
- Updated code to deal with special XML characters
*******************************************************************************/
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
WITH
E1(N) AS (SELECT N FROM (VALUES (NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL)) AS X(N)),
itally(N) AS
(
SELECT TOP(CONVERT(INT,LEN(@String),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM E1 T1 CROSS JOIN E1 T2 CROSS JOIN E1 T3 CROSS JOIN E1 T4
)
SELECT NewString =
((
SELECT SUBSTRING(@String,N,1)
FROM iTally
WHERE 0 = PATINDEX(@Pattern,SUBSTRING(@String COLLATE Latin1_General_BIN,N,1))
FOR XML PATH(''),TYPE
).value('.[1]','varchar(8000)'));
GO
Вот адаптация, которую вы можете использовать.
WITH E1(N) AS (
SELECT N FROM (VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) AS X(N)
)
SELECT ProductData.Customer_ID,
CASE
WHEN ProductData.Product_Title = 'A_Title' AND ProductData.Product_Category != 'A_Category' THEN x.NewString
WHEN ProductData.Product_Category = 'A_Category' THEN 'A_Category'
ELSE 'R_Category' END AS R_Category
FROM ProductData
CROSS APPLY (SELECT NewString =((SELECT SUBSTRING(Product_Category,N,1)
FROM (
SELECT TOP(CONVERT(INT,LEN(Product_Category),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM E1 T1, E1 T2, E1 T3, E1 T4) AS iTally(N)
WHERE 0 = PATINDEX('%[^a-zA-Z ]%',SUBSTRING(Product_Category COLLATE Latin1_General_BIN,N,1))
FOR XML PATH(''),TYPE).value('.[1]','varchar(8000)'))) AS x;
Как уже упоминали Шон и, возможно, другие, вам следует постоянно очищать данные, а не чистить каждый раз, когда вы их потребляете. Предыдущий оператор SELECT может быть легко преобразован в ОБНОВЛЕНИЕ.
WITH E1(N) AS (
SELECT N FROM (VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) AS X(N)
)
UPDATE ProductData SET
Product_Category = CASE
WHEN ProductData.Product_Title = 'A_Title' AND ProductData.Product_Category != 'A_Category' THEN x.NewString
WHEN ProductData.Product_Category = 'A_Category' THEN 'A_Category'
ELSE 'R_Category' END
FROM ProductData
CROSS APPLY (SELECT NewString =((SELECT SUBSTRING(Product_Category,N,1)
FROM (
SELECT TOP(CONVERT(INT,LEN(Product_Category),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM E1 T1, E1 T2, E1 T3, E1 T4) AS iTally(N)
WHERE 0 = PATINDEX('%[^a-zA-Z ]%',SUBSTRING(Product_Category COLLATE Latin1_General_BIN,N,1))
FOR XML PATH(''),TYPE).value('.[1]','varchar(8000)'))) AS x;
SELECT * FROM ProductData;