How to join element values in XQuery for SQL Server? - sql-server

Question

If I have this XML
<TradingInquirySearchResult xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<SearchTerm>test</SearchTerm>
<CompanyFound>true</CompanyFound>
<CompanyInfoCollection>
<CompanyInfo>
<CompanyID>26</CompanyID>
<CompanyName>test</CompanyName>
<Status>Unrestricted</Status>
<SearchTags>
<Tag>test2</Tag>
<Tag>test3</Tag>
<Tag>test4</Tag>
</SearchTags>
</CompanyInfo>
</CompanyInfoCollection>
</TradingInquirySearchResult>
I want to get "test2;test3;test4". How can I join the values of <Tag> for the first <CompanyInfo> tag?
I tried TransactionData.value('(/TradingInquirySearchResult/CompanyInfoCollection/CompanyInfo[1]/SearchTags/Tag)[1]', 'nvarchar(1000)')
but it didn't work.
Thanks

Answer 1

As you're using SQL Server 2012 (or rather not 2017+) the common way to aggregate strings is to use FOR XML PATH and STUFF, and you can get the multiple values for the node Tag using the nodes operator. This gives you the below:
DECLARE #XML xml = '
<TradingInquirySearchResult xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<SearchTerm>test</SearchTerm>
<CompanyFound>true</CompanyFound>
<CompanyInfoCollection>
<CompanyInfo>
<CompanyID>26</CompanyID>
<CompanyName>test</CompanyName>
<Status>Unrestricted</Status>
<SearchTags>
<Tag>test2</Tag>
<Tag>test3</Tag>
<Tag>test4</Tag>
</SearchTags>
</CompanyInfo>
</CompanyInfoCollection>
</TradingInquirySearchResult>';
SELECT STUFF((SELECT N';' + ST.Tag.value('(./text())[1]','nvarchar(100)')
FROM (VALUES(#XML))V(X)
CROSS APPLY V.X.nodes('/TradingInquirySearchResult/CompanyInfoCollection/CompanyInfo/SearchTags/Tag') ST(Tag)
FOR XML PATH(N''),TYPE).value('.','nvarchar(MAX)'),1,1,N'') AS Tags
Edit for guess when multiple companies.
If you only want the first company, then yes, using [1] would work:
DECLARE #XML xml = '
<TradingInquirySearchResult xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<SearchTerm>test</SearchTerm>
<CompanyFound>true</CompanyFound>
<CompanyInfoCollection>
<CompanyInfo>
<CompanyID>26</CompanyID>
<CompanyName>test</CompanyName>
<Status>Unrestricted</Status>
<SearchTags>
<Tag>test2</Tag>
<Tag>test3</Tag>
<Tag>test4</Tag>
</SearchTags>
</CompanyInfo>
<CompanyInfo>
<CompanyID>27</CompanyID>
<CompanyName>Sample</CompanyName>
<Status>Restricted</Status>
<SearchTags>
<Tag>test6</Tag>
<Tag>test7</Tag>
<Tag>test8</Tag>
</SearchTags>
</CompanyInfo>
</CompanyInfoCollection>
</TradingInquirySearchResult>';
SELECT STUFF((SELECT N';' + ST.Tag.value('(./text())[1]','nvarchar(100)')
FROM (VALUES(#XML))V(X)
CROSS APPLY V.X.nodes('/TradingInquirySearchResult/CompanyInfoCollection/CompanyInfo[1]/SearchTags/Tag') ST(Tag)
FOR XML PATH(N''),TYPE).value('.','nvarchar(MAX)'),1,1,N'') AS Tags;
If, however, you want a row per company, then you would want to do something like this:
SELECT CIC.CI.value('(./CompanyID/text())[1]','nvarchar(50)') AS CompanyID,
STUFF((SELECT N';' + ST.Tag.value('(./text())[1]','nvarchar(100)')
FROM CIC.CI.nodes('./SearchTags/Tag') ST(Tag)
FOR XML PATH(N''),TYPE).value('.','nvarchar(MAX)'),1,1,N'') AS Tags
FROM (VALUES(#XML))V(X)
CROSS APPLY V.X.nodes('/TradingInquirySearchResult/CompanyInfoCollection/CompanyInfo') CIC(CI);