我在一个包含食品的餐桌上,食品可以分开;或者,字段大小可以是不同的长度。
"Milk - 2%; Peanut Butter and Jelly Sandwich; Fruit Cocktail"
"oatmeal cookies ; Milk - Whole"
"Peanut Butter and Jelly Sandwich"
这是我对第一行所做的,但是有更简单的方法吗?
DECLARE @Food VARCHAR(100)
SET @Food = 'Cottage Cheese (1/2 cup); Fruit Cocktail, apple juice'
SELECT SUBSTRING(@FOOD,1,CHARINDEX(';', @FOOD)-1)
SELECT SUBSTRING(@FOOD,27,CHARINDEX(',', @FOOD)-27)
SELECT SUBSTRING(@FOOD,42,CHARINDEX(',', @FOOD)-1)
答案 0 :(得分:1)
您可能希望为此使用字符串拆分器。这是来自Aaron Bertrand的article:
CREATE FUNCTION dbo.SplitStrings_XML
(
@List NVARCHAR(MAX),
@Delimiter NVARCHAR(255)
)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
(
SELECT Item = y.i.value('(./text())[1]', 'nvarchar(4000)')
FROM
(
SELECT x = CONVERT(XML, '<i>'
+ REPLACE(@List, @Delimiter, '</i><i>')
+ '</i>').query('.')
) AS a CROSS APPLY x.nodes('i') AS y(i)
);
GO
您的最终查询将是:
SELECT
t.Id,
LTRIM(RTRIM(c.Item))
FROM tbl t
CROSS APPLY dbo.SplitStrings_XML(t.food, ';') sc
CROSS APPLY dbo.SplitStrings_XML(sc.Item, ',') c
另一种方法是使用基于模式的分割器。这是来自Dwain Camp的article
-- PatternSplitCM will split a string based on a pattern of the form
-- supported by LIKE and PATINDEX
--
-- Created by: Chris Morris 12-Oct-2012
CREATE FUNCTION [dbo].[PatternSplitCM]
(
@List VARCHAR(8000) = NULL
,@Pattern VARCHAR(50)
) RETURNS TABLE WITH SCHEMABINDING
AS
RETURN
WITH numbers AS (
SELECT TOP(ISNULL(DATALENGTH(@List), 0))
n = ROW_NUMBER() OVER(ORDER BY (SELECT NULL))
FROM
(VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) d (n),
(VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) e (n),
(VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) f (n),
(VALUES (0),(0),(0),(0),(0),(0),(0),(0),(0),(0)) g (n)
)
SELECT
ItemNumber = ROW_NUMBER() OVER(ORDER BY MIN(n)),
Item = SUBSTRING(@List,MIN(n),1+MAX(n)-MIN(n)),
[Matched]
FROM (
SELECT n, y.[Matched], Grouper = n - ROW_NUMBER() OVER(ORDER BY y.[Matched],n)
FROM numbers
CROSS APPLY (
SELECT [Matched] = CASE WHEN SUBSTRING(@List,n,1) LIKE @Pattern THEN 1 ELSE 0 END
) y
) d
GROUP BY [Matched], Grouper
您的最终查询将是:
SELECT
t.Id,
LTRIM(RTRIM(s.Item))
FROM tbl t
CROSS APPLY dbo.PatternSplitCM(t.food, '%[;,]%') s
WHERE s.Matched = 0