我正在尝试使用Tag搜索,并且它主要使用LIKE Tag匹配的例外.
我已将示例代码添加到SQLFiddle以进行播放,并在此处包含它:
表和数据
CREATE TABLE Attendees ( Id INT,Text VARCHAR(500) ); CREATE TABLE Tags ( Id INT,Description VARCHAR(50) ); CREATE TABLE AttendeeTags ( AttendeeId INT,TagId INT,Value VARCHAR(50) ); INSERT INTO Attendees VALUES (1,'Attendee 1'); INSERT INTO Attendees VALUES (2,'Attendee 2'); INSERT INTO Tags VALUES (1,'Tag Name 1'); INSERT INTO Tags VALUES (2,'Tag Name 2'); INSERT INTO AttendeeTags VALUES (1,1,'Value 1'); INSERT INTO AttendeeTags VALUES (1,'Value 2'); INSERT INTO AttendeeTags VALUES (1,2,'Value 2'); INSERT INTO AttendeeTags VALUES (2,'Value 1');
询问
DECLARE @MandatoryTagXml XML SET @MandatoryTagXml = '<tags><tag><description>Tag Name 1</description><value>Value 2</value></tag></tags>' ;WITH MandatoryTags AS ( SELECT TagValue.value('(./value)[1]','nvarchar(100)') AS value,TagValue.value('(./description)[1]','nvarchar(100)') AS [description] FROM @MandatoryTagXml.nodes('/tags/tag') AS T(TagValue) ) SELECT DISTINCT A.Id [AttendeeId] FROM [dbo].[Attendees] A INNER JOIN [dbo].[AttendeeTags] AT ON AT.AttendeeId = AttendeeId INNER JOIN [dbo].[Tags] T ON T.Id = AT.TagId AND T.[Description] IN (SELECT [description] FROM MandatoryTags) WHERE NOT EXISTS ( SELECT T.Id,c.value FROM MandatoryTags c JOIN Tags T ON c.[description] = T.[Description] -- Add LIKE match to value - This is the problem line JOIN AttendeeTags AT ON AT.Value LIKE '%' + C.[Value] + '%' EXCEPT SELECT ATT.TagId,ATT.Value FROM [AttendeeTags] ATT WHERE ATT.AttendeeId = A.Id )
我想要的是在Tags.Description与@MandatoryTagXml中的描述完全匹配时获得结果,并且AttendeeTags.Value与@MandatoryTagXml中提供的值相似
没有以下行就能按预期工作(即,当XML完全匹配时)
JOIN AttendeeTags AT ON AT.Value LIKE '%' + C.[Value] + '%'
但是当我加入它时,我开始得到不正确的结果.例如,设置Value应返回Attendee.Id,但它不会返回任何结果.
我尝试过各种EXISTS和NOT EXISTS,EXCEPT和INTERSECT等组合,但无法在所有情况下都能使用它.
谁能提供任何关于如何使其工作的建议?
解决方法
我认为你的联系比需要的更复杂……
DECLARE @MandatoryTagXml XML SET @MandatoryTagXml = ' <tags> <tag><description>Tag Name 1</description><value>Value 1</value></tag> <tag><description>Tag Name 2</description><value>Value 2</value></tag> </tags>' ;WITH MandatoryTags AS ( SELECT TagValue.value('(./value)[1]','nvarchar(100)') AS [description] FROM @MandatoryTagXml.nodes('/tags/tag') AS T(TagValue) ) SELECT A.Id [AttendeeId] FROM [dbo].[Attendees] A INNER JOIN [dbo].[AttendeeTags] AT INNER JOIN [dbo].[Tags] T ON T.Id = AT.TagId ON AT.AttendeeId = A.Id INNER JOIN MandatoryTags m ON T.Description = m.Description AND AT.Value LIKE ('%' + m.Value + '%') GROUP BY A.Id -- Make sure that all of the tags are matched HAVING COUNT(*) = (SELECT COUNT(*) FROM MandatoryTags)