[Solved] Fastest SQL query for non-indexed data

How to optimize this SQL query?

In case you have your own slow SQL query, you can optimize it automatically here.

For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:

  1. Description of the steps you can take to speed up the query.
  2. The optimal indexes for this query, which you can copy and create in your database.
  3. An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
  1. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.
  2. Use Numeric Column Types For Numeric Values (query line: 12): Referencing a numeric value (e.g. 34818) as a string in a WHERE clause might result in poor performance. Possible impacts of storing numbers as varchars: more space will be used, you won't be able to perform arithmetic operations, the data won't be self-validated, aggregation functions like SUM won't work, the output may sort incorrectly and more. If the column is numeric, remove the quotes from the constant value, to make sure a numeric comparison is done.
Optimal indexes for this query:
CREATE INDEX windowsevent_idx_devicei_severit_eventlo_timeofe ON WindowsEvent (DeviceID,Severity,EventLog,TimeOfEvent);
CREATE INDEX windowsevent_idx_devic_sever_event_event_event_descr ON WindowsEvent (DeviceID,Severity,EventLog,EventID,EventSource,Description);
The optimized query:
SELECT
        COUNT(*) AS NumOcc,
        WindowsEvent.EventID,
        WindowsEvent.EventLog,
        WindowsEvent.EventSource,
        WindowsEvent.Severity,
        WindowsEvent.TimeOfEvent,
        WindowsEvent.Description 
    FROM
        WindowsEvent 
    WHERE
        WindowsEvent.DeviceID = '34818' 
        AND WindowsEvent.Severity = 1 
        AND WindowsEvent.TimeOfEvent >= DATEADD(hh, DATEDIFF(hh, GETDATE(), GETUTCDATE()), '2010/10/27 12:00:00 AM') 
        AND WindowsEvent.TimeOfEvent <= DATEADD(hh, DATEDIFF(hh, GETDATE(), GETUTCDATE()), '2010/11/3 12:00:00 AM') 
        AND WindowsEvent.EventID <> 34113 
        AND WindowsEvent.EventID <> 34114 
        AND WindowsEvent.EventID <> 34112 
        AND WindowsEvent.EventID <> 57755 
        AND WindowsEvent.EventSource <> 'AutoImportSvc.exe' 
        AND WindowsEvent.EventLog = 'Application' 
    GROUP BY
        WindowsEvent.EventID,
        WindowsEvent.EventLog,
        WindowsEvent.EventSource,
        WindowsEvent.Severity,
        WindowsEvent.Description 
    ORDER BY
        NumOcc DESC

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* original question posted on StackOverflow here.