[Solved] Occasional failure of sub-query on SQL Server using ADO - properties not supported

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. Avoid Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
  2. Avoid Subselect When Selecting MAX/MIN Per Group (query line: 9): Constant subquery results are usually not cached by the database, especially in non-recent database versions. Therefore, a constant subquery in a WHERE clause will be fully evaluated for every row the WHERE clause will examine, which can significantly impact query performance. Use the method mentioned in the example instead.
  3. 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.
Optimal indexes for this query:
CREATE INDEX packs_idx_machid_packid_buildid ON Packs (MachID,PackID,BuildID);
The optimized query:
        Packs AS Packs1 
        packs AS packs2 
            ON (
                packs2.BuildID = Packs1.BuildID 
                AND packs2.MachID = Packs1.MachID
            AND (
                Packs1.PackID < packs2.PackID
            Packs1.MachID = :MachID 
            AND Packs1.BuildID <= :MaxPosID 
            AND 1 = 1
        AND (
            packs2.PackID IS NULL

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* original question posted on StackOverflow here.