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POHow do I query for a max value and return date found
 

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  1. POHow do I query for a max value and return date found
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    <p>I am trying to query for a maximium value from 5am to 5am the next morning. I would also like to have the start of query date in the results. </p> <p>here is what I have so far</p> <pre><code> Select Max(Value) as RWQ22003DTDDS from History WHERE Datetime&gt;='2009-08-21 05:00:00' AND Datetime&lt;='2009-08-22 05:00:00' and Tagname ='RWQ22003DTDDS' </code></pre> <p>I would like the date of "2009-08-21" to be in the results.</p> <pre><code>datetime, value ------------------ 2008-08-21, 2216 2008-08-20, 4312 </code></pre> <p>etc. and to do this for 7 days previous</p> <p>UPDATE :</p> <p>here's another approch I came up with</p> <pre><code> declare @dec int declare @SqlQry as varchar(4000) declare @dd as nvarchar(50) declare @ResolvedQry as varchar(4000) set @dec = 0 set @SqlQry ='' WHILE (@dec &lt;= 7) BEGIN set @dd = cast(datepart(mm,getdate()-@dec)as nvarchar) +'/'+ cast(datepart(dd,getdate()-@dec)as nvarchar) +'/'+ cast(datepart(yyyy,getdate()-@dec) as nvarchar)+' 06:00:00' set @ResolvedQry = ' Select cast( convert(datetime,'''+@dd+''',102) as datetime) as [Date], Max(Value) as RWQ22003DTDDS from History WHERE Datetime&gt;='''+ convert(varchar, dateadd(mi,5,convert(datetime,@dd,102))) + ''' and Datetime&lt;='''+ convert(varchar, dateadd(mi,-5,convert(datetime,@dd,102)+1)) +''' and Tagname =''RWQ22003DTDDS''' if(@dec &lt;7) begin set @ResolvedQry =@ResolvedQry + ' union' end set @SqlQry = @SqlQry + @ResolvedQry set @dec = @dec + 1 END set @SqlQry ='select * from ( ' + @SqlQry + ') as dt order by [Date] desc' print @SqlQry exec(@SqlQry) </code></pre> <p>results:</p> <pre><code> Date RWQ22003DTDDS ------------------- ---------------------- Aug 21 2009 5:00AM 3586 Aug 20 2009 5:00AM 7233 Aug 19 2009 5:00AM 9099 Aug 18 2009 5:00AM 9099 Aug 17 2009 5:00AM 8909 Aug 16 2009 5:00AM 8516 Aug 15 2009 5:00AM 8064 Aug 14 2009 5:00AM 7437 </code></pre> <p>Comments?</p>
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      1. POHow do I query for a max value and return date found
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    1. COThere's not enough detail in this question. A schema of the table(s) involved and some same data and expected output is needed to answer the question completely.
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      1. USWelbog
    2. COYou really need to elaborate here. What exactly are you having problems with?
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      1. USJimmeh
    3. COWhat is the schema for the database that you are using?
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      1. USBobBrez
 

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