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    <p>There are several different ways that you can get the result, you can use an aggregate function with a CASE expression or you can use the PIVOT function to get this. Based on your comment that any number of fields can be defined, it sounds like you will need to use dynamic SQL to get the final result. Before writing a dynamic SQL version, I would always start with a static or hard-coded version of the query, then convert it to dynamic SQL.</p> <p>Besides using these methods, I would also recommend using the windowing function <code>row_number()</code> to generate a unique value for each combination of <code>userid</code> and <code>fieldname</code>. Since you are pivoting string values, then you have to use either the <code>max</code>/<code>min</code> aggregate function which will return only one value for each fieldname, by adding the row_number you will be able to return multiple combinations of <code>Location</code>, etc for each user.</p> <p>If you were using an aggregate function with a CASE expression the query would be:</p> <pre><code>select userid, max(case when userfieldname = 'Location' then userfieldvalue end) location, max(case when userfieldname = 'Color' then userfieldvalue end) Color from ( select v.userid, f.userfieldname, v.userfieldvalue, row_number() over(partition by v.userid, v.userfieldid order by v.userfieldid) seq from userFields f left join userValues v on f.userfieldId = v.userFieldId ) d group by userid, seq order by userid; </code></pre> <p>See <a href="http://sqlfiddle.com/#!3/fa5ab/8" rel="nofollow">SQL Fiddle with Demo</a></p> <p>If you were using PIVOT, the hard-coded version of the query would be:</p> <pre><code>select userid, Location, Color from ( select v.userid, f.userfieldname, v.userfieldvalue, row_number() over(partition by v.userid, v.userfieldid order by v.userfieldid) seq from userFields f left join userValues v on f.userfieldId = v.userFieldId ) d pivot ( max(userfieldvalue) for userfieldname in (Location, Color) ) p order by userid; </code></pre> <p>See <a href="http://sqlfiddle.com/#!3/fa5ab/4" rel="nofollow">SQL Fiddle with Demo</a>.</p> <p>Once you have the correct logic you can convert the PIVOT to dynamic SQL to be executed:</p> <pre><code>DECLARE @cols AS NVARCHAR(MAX), @query AS NVARCHAR(MAX) select @cols = STUFF((SELECT ',' + QUOTENAME(UserFieldName) from UserFields group by UserFieldName, userfieldId order by userfieldid FOR XML PATH(''), TYPE ).value('.', 'NVARCHAR(MAX)') ,1,1,'') set @query = 'SELECT userid, ' + @cols + ' from ( select v.userid, f.userfieldname, v.userfieldvalue, row_number() over(partition by v.userid, v.userfieldid order by v.userfieldid) seq from userFields f left join userValues v on f.userfieldId = v.userFieldId ) x pivot ( max(userfieldvalue) for userfieldname in (' + @cols + ') ) p order by userid' execute sp_executesql @query; </code></pre> <p>See <a href="http://sqlfiddle.com/#!3/fa5ab/7" rel="nofollow">SQL Fiddle with Demo</a>. All versions will give a result:</p> <pre><code>| USERID | LOCATION | COLOR | |--------|----------|--------| | 1 | Home | Orange | | 1 | Office | (null) | | 2 | Office | Red | </code></pre>
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    1. COThanks a TON. That worked like a charm, and helped me understand as well.
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      1. USChristopher Nobles
    2. CO@GarethD however the variable assignment method is unpredictable and non-deterministic - the order of assignment is not guaranteed, so you could get different output between executions, and I believe there are scenarios where you could miss rows, too. FOR XML PATH is deterministic as long as you have an ORDER BY. Also, comparing two queries by looking only at % of query cost is a joke. CPU, reads and duration are metrics that are thousands of times more valuable. In any case, when comparing a query that works to a query that might work, I don't care which one is faster, I value correct first.
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      1. USAaron Bertrand
    3. COI stand very much corrected. I have always used the XML PATH method but I came across an instance recently where changing to using the variable assignment method and it improved performance no end, so dug a little deeper and the as has been mentioned the execution plan gave very little away about the XML methods, since the IO was the same, and the CPU cost more with the for XML method, I was left to assume the additional cost of the query came from the XML reader table valued function. I live and I learn, hopefully I won't stop learning.
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