我有一个很长的NVARCHAR变量,我需要替换这样的模式：
DECLARE @data NVARCHAR(200) = 'Hello [PAT1] stackoverflow [PAT2] world [PAT3]'
我需要用空格替换所有[PAT％],如下所示：
'Hello stackoverflow world'
如何在sql Server 2008中使用T-sql执行此操作？
我正在寻找其他问题,我只找到了this,但它对我没有帮助,因为我不需要保留字符串的原始部分.
解决方法
您可以使用此功能进行图案替换.您可以使用此
SQL-Fiddle demo进行测试以进行测试.
CREATE FUNCTION dbo.PatternReplace
(
@InputString VARCHAR(4000),@Pattern VARCHAR(100),@ReplaceText VARCHAR(4000)
)
RETURNS VARCHAR(4000)
AS
BEGIN
DECLARE @Result VARCHAR(4000) SET @Result = ''
-- First character in a match
DECLARE @First INT
-- Next character to start search on
DECLARE @Next INT SET @Next = 1
-- Length of the total string -- 8001 if @InputString is NULL
DECLARE @Len INT SET @Len = COALESCE(LEN(@InputString),8001)
-- End of a pattern
DECLARE @EndPattern INT
WHILE (@Next <= @Len)
BEGIN
SET @First = PATINDEX('%' + @Pattern + '%',SUBSTRING(@InputString,@Next,@Len))
IF COALESCE(@First,0) = 0 --no match - return
BEGIN
SET @Result = @Result +
CASE --return NULL,just like REPLACE,if inputs are NULL
WHEN @InputString IS NULL
OR @Pattern IS NULL
OR @ReplaceText IS NULL THEN NULL
ELSE SUBSTRING(@InputString,@Len)
END
BREAK
END
ELSE
BEGIN
-- Concatenate characters before the match to the result
SET @Result = @Result + SUBSTRING(@InputString,@First - 1)
SET @Next = @Next + @First - 1
SET @EndPattern = 1
-- Find start of end pattern range
WHILE PATINDEX(@Pattern,@EndPattern)) = 0
SET @EndPattern = @EndPattern + 1
-- Find end of pattern range
WHILE PATINDEX(@Pattern,@EndPattern)) > 0
AND @Len >= (@Next + @EndPattern - 1)
SET @EndPattern = @EndPattern + 1
--Either at the end of the pattern or @Next + @EndPattern = @Len
SET @Result = @Result + @ReplaceText
SET @Next = @Next + @EndPattern - 1
END
END
RETURN(@Result)
END
