How can I optimize my SQL query to run faster?

Question

SELECT 
   b.User_Id
   ,(CONVERT(varchar, DATEADD(hh, - 7, b.callstartdt), 101))as 'Dt'
   ,(COUNT(distinct b.SeqNum ) + Count(distinct c.SeqNum) + count(distinct d.seqnum)) as 'TotalCalls'
   ,COUNT(distinct b.SeqNum )as 'ACD'
   ,COUNT(distinct c.SeqNum)as 'AOD'
   ,COUNT(distinct d.seqnum)  as 'Manual'
   ,COUNT(distinct e.SeqNum)as 'Contacts'
   ,COUNT (distinct es.seqnum) as 'Success'
FROM 
   [detail_epro].[dbo].[ACDCallDetail]as b 
LEFT JOIN 
   [detail_epro].[dbo].[AODCallDetail]as c on c.User_Id = b.User_Id   
LEFT JOIN
   [detail_epro].[dbo].[manualCallDetail]as d on d.User_Id = b.User_Id 
LEFT JOIN
   (SELECT 
       USER_ID, CallStartDt, SeqNum
    FROM 
       [detail_epro].[dbo].[AgentDispoDetail]
    WHERE 
        Disp_Id IN 
                (100000150, 100000126,  100000137,  100000093,  100000133,  
                100000123,  100000094,  100000161,  100000162,  100000085,  
                100000084,  100000086,  100000096,  100000087,  100000157,  
                100000088,  100000097,  100000154,  100000148,  100000134,  
                100000131,  100000160,  100000156,  100000165,  100000166,  
                100000122,  100000121,  100000138,  100000130,  100000144,  
                100000132,  100000158,  100000098,  100000147,  100000100,  
                100000153,  100000139,  100000145,  100000101,  100000140,  
                100000102,  100000103,  100000104,  100000105,  100000106,  
                100000159,  100000112,  100000135,  100000090,  100000113,  
                100000141,  100000146,  100000115,  100000108,  100000092,  
                100000155,  100000125,  100000151,  100000136,  100000107,  
                100000142) 
   ) AS e ON e.User_Id = b.User_Id
LEFT JOIN 
   (SELECT 
        USER_ID, CallStartDt, SeqNum
    FROM 
        [detail_epro].[dbo].[AgentDispoDetail]
    WHERE Disp_Id IN 
                (100000150, 100000137,  100000093,  100000133,  100000123,  
                100000094,  100000161,  100000085,  100000086,  100000157,  
                100000088,  100000131,  100000160,  100000156,  100000165,  
                100000166,  100000122,  100000121,  100000138,  100000144,  
                100000132,  100000098,  100000100,  100000153,  100000139,  
                100000145,  100000101,  100000140,  100000102,  100000103,  
                100000105,  100000106,  100000159,  100000112,  100000135,  
                100000141,  100000146,  100000115,  100000108,  100000092,  
                100000155,  100000125,  100000151,  100000136,  100000107) 
   ) AS es ON es.User_Id = b.User_Id
WHERE
   (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101)) = (CONVERT(varchar, DATEADD(hh, - 7, c.CallStartDt), 101))
   AND (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101))= (CONVERT(varchar, DATEADD(hh, - 7, d.CallStartDt), 101))
   AND (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101))= (CONVERT(varchar, DATEADD(hh, - 7, e.CallStartDt), 101)) 
   AND (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101))= (CONVERT(varchar, DATEADD(hh, - 7, es.CallStartDt), 101))
   AND (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101)) >= '08/01/2014'
GROUP BY
   b.User_Id, b.CallStartDt

It's taking a lot longer than I would like to run this query, over a minute, I'm guessing it has a lot to do with the server but figured I would ask to see if anyone had any thoughts of making this faster

The query is to get some phone agent data, that isn't summarized by any tables

• acd = inbound calls
• aod = dialer calls
• manual = manual calls
• contacts = are based on the disposition codes an agent would use
• success = is a subset of contacts

Answer 1

There are numerous issues with the query but the first thing I notice is the inefficient datetime conversions. So, I'd start with that part first, before examining the indexing and the execution plan.

I suppose you want to check if the various datetimes are in the same date (minus the 7 hours which is probably your timezone while the data are stored in UTC). So, lets try this, instead of that (horrible) WHERE :

CROSS APPLY
    ( SELECT dt = DATEADD(hour, -7, b.CallStartDt) ) AS x
CROSS APPLY
    ( SELECT dt = DATEADD(day, +1, x.dt) ) AS y
WHERE
       b.CallStartDt >= DATEADD(hour, +7, '20140801')
  AND  c.CallStartDt >= x.dt AND  c.CallStartDt < y.dt
  AND  d.CallStartDt >= x.dt AND  d.CallStartDt < y.dt
  AND  e.CallStartDt >= x.dt AND  e.CallStartDt < y.dt
  AND es.CallStartDt >= x.dt AND es.CallStartDt < y.dt

Explanation/notes:

• the (CONVERT(varchar, DATEADD(hh, - 7, b.CallStartDt), 101)) >= '08/01/2014' is utterly wrong. Not only it uses inefficient conversions, it will also return wrong results. Because the date (both as string and as date) '08/03/2014' is after '08/01/2014' but for other examples, it's the other way around: '09/09/2011' > '08/01/2014' but obviously 2011 is before 2014.

• All unnecessary calls to DATEDIFF() and CONVERT() have been removed. This way, not only several thousands calls (or million, depends on your tables sizes) to the functions will not be done but the optimizer will be able to use indexes for the various conditions, if there are indexes on these columns.

• Only the (-7 hours) of b.CallStartDt has been kept as there is no way to avoid that without altering the table (adding a computed column with an index though would help.)

• Use sane formats for dates and datetimes, like '20140801' ( 'YYYYMMDD' ), which as Aaron Bertrand's blog explains is the only 100% secure format for using with dates in SQL-Server. See: Bad habits to kick : mis-handling date / range queries

• With the DATEADD() function, use the long forms. hour instead of hh , day instead of dd , minute instead of mm (or is it mi ?, or min ?, I keep forgetting.) Less error-prone.

More to do:

• The 4 above conditions (the ones regarding c , d , e and es tables) should probably be moved to the respective LEFT joins (as DRapp commented.)

• Check the execution plan and whether indexes are available and used.

Minor details:

• Avoid single quotes aliases. use either unquoted aliases, or double-quoted if needed. See (another Aaron Bertrand's blog post): Bad Habits to Kick : Using AS instead of = for column aliases

Answer 2

You need to remove your subqueries and put

WHERE Disp_Id IN 
(100000150, 100000137,  100000093,  100000133,  100000123,  
100000094,  100000161,  100000085,  100000086,  100000157,  
100000088,  100000131,  100000160,  100000156,  100000165,  
100000166,  100000122,  100000121,  100000138,  100000144,  
100000132,  100000098,  100000100,  100000153,  100000139,  
100000145,  100000101,  100000140,  100000102,  100000103,  
100000105,  100000106,  100000159,  100000112,  100000135,  
100000141,  100000146,  100000115,  100000108,  100000092,  
100000155,  100000125,  100000151,  100000136,  100000107)

In a temp table and join that temp table to [detail_epro].[dbo].[AgentDispoDetail] on Disp_ID.

And as others have already posted, why are you using converts to compare the dates? Are they in a different format on each table? If they aren't remove the converts.

Also, remove the DATEADDS. You are using them in a comparison, but adding -7 to each half of the equation. That is like: X + 7 = 8 + 7. Remove the 7s and the value of x hasn't changed.

Answer 3

Just as an update since i didnt post an answer, I ended up seprating a lot of the queries into smaller queries with temp tables, doing this sped up the query and the process 1000%

eventually converted to CTE and saved it as a view

Thanks all

Answer 4

Not sure of your locale but a better UTC conversion you might want to consider is

    dateadd(minute, datediff(minute, sysutcdatetime(), sysdatetime()), b.callstartdt)

which also accounts for daylight savings, again depending on your locale.