我有一个包含RxDir
和RxNum
列的表Dir
。 Dir
由用户输入的文本组成,该文本是快速代码和自由文本的组合。快速代码存储在SCodes
列下的SCode
表格中。
我需要在给定RxNum
时创建方向的扩展结果。如果Dir
包含
LYLAS BUT OMG YOU HAVE VD & BEANS
然后我需要将结果解释为
LOVE YOU LIKE A SISTER BUT OH MY GOODNESS YOU HAVE VIENNA DOGS & BEANS
(假设明显的首字母存储在SCodes
中,而完整的单词则不存在。)
答案 0 :(得分:3)
你想要的第一件事是字符串分割器。这是DelimitedSplit8K
,是最快的分裂器之一。
CREATE FUNCTION [dbo].[DelimitedSplit8K](
@pString VARCHAR(8000), @pDelimiter CHAR(1)
)
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
WITH E1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
)
,E2(N) AS (SELECT 1 FROM E1 a, E1 b)
,E4(N) AS (SELECT 1 FROM E2 a, E2 b)
,cteTally(N) AS(
SELECT TOP (ISNULL(DATALENGTH(@pString), 0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
)
,cteStart(N1) AS(
SELECT 1 UNION ALL
SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString, t.N, 1) = @pDelimiter
),
cteLen(N1, L1) AS(
SELECT
s.N1,
ISNULL(NULLIF(CHARINDEX(@pDelimiter, @pString, s.N1),0) - s.N1, 8000)
FROM cteStart s
)
SELECT
ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
Item = SUBSTRING(@pString, l.N1, l.L1)
FROM cteLen l
现在,您想要的是将每个Dir
与' '
分开作为分隔符。使用您的样本数据和上面的函数
SELECT * FROM dbo.DelimitedSplit8K('LYLAS BUT OMG YOU HAVE VD & BEANS', ' ')
结果是:
ItemNumber Item
----------- ----------
1 LYLAS
2 BUT
3 OMG
4 YOU
5 HAVE
6 VD
7 &
8 BEANS
使用上述结果,您现在可以在LEFT JOIN
上执行SCodes
来获取每个ExTxt
的含义或Item
。然后将ExTxt
连接起来以获得所需的结果。
最终查询将是:
SELECT
rd.RxNum,
rd.Dir,
Result =
STUFF((
SELECT ' ' + ISNULL(sc.ExTxt, x.Item)
FROM dbo.DelimitedSplit8K(rd.Dir, ' ' ) x
LEFT JOIN SCodes sc
ON sc.SCode = x.Item
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),
1, 1, '')
FROM RxDir rd
<强> RESULT 强>
| RxNum | Dir | Result |
|-------|-----------------------------------|-----------------------------------------------------------------------|
| 1 | LYLAS BUT OMG YOU HAVE VD & BEANS | LOVE YOU LIKE A SISTER BUT OH MY GOODNESS YOU HAVE VIENA DOGS & BEANS |
注意:请参阅Aaron Bertrand的article了解其他字符串拆分器。