[Solved] Indexing strategy for a query involving three views, multiple columns and several JOINs

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. Use UNION ALL instead of UNION (query line: 21): Always use UNION ALL unless you need to eliminate duplicate records. By using UNION ALL, you'll avoid the expensive distinct operation the database applies when using a UNION clause.
The optimized query:
SELECT
        V1.Live_DataIdx,
        V1.DTLive1,
        V1.DTLive2,
        V1.DTLive3,
        V1.DTLive4,
        V1.DTDelivery,
        V1.DTData2,
        V1.DTLive5,
        V1.DTData3,
        V1.DTData4,
        V1.Desc,
        V1.Counter,
        V1.DataFormat,
        V1.DataType,
        V1.Live_QueueIdx,
        V1.Live_QueueGUID 
    FROM
        V1 
    UNION
    SELECT
        V2.History_DataIdx,
        V2.DTLive1,
        V2.DTLive2,
        V2.DTLive3,
        V2.DTLive4,
        V2.DTDelivery,
        V2.DTData2,
        V2.DTLive5,
        V2.DTData3,
        V2.DTData4,
        V2.Desc,
        V2.Counter,
        V2.DataFormat,
        V2.DataType,
        V2.live_QueueIdx,
        V2.Live_QueueGUID 
    FROM
        V2

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* original question posted on StackOverflow here.