As I mentioned in the last post, I’m taking you through our adventure in upgrading the existing on-premise Dynamics CRM 2011 environment to 2016 (and eventually 2016 cloud). Previously I discussed the first show-stopper error we received, “Must declare the scalar variable “@table”.” Following that resolution the import continued past the stage “Metadata xml upgrade: pass 1” but then failed at “Upgrade Indexes”.
Through the use of trace logs obtained by using the CRM diagnostic tool, we discovered that the import wizard was marking a number of indexes to be dropped and then recreated. However, as observed through a SQL Profiler deadlock trace, it was trying to drop and add indexes on the same table at the same time. As I mentioned in my previous post, our database is in excess of 1.5TB. One of the largest tables is ActivityPointerBase, and it’s also one on which many index operations were being executed by the import wizard. The result is that some of the index operations would be chosen as the deadlock victim, causing the import wizard to throw an error and exit. Also, if you restarted the import it would process the entire list again, not taking into account any that it had dropped and recreated already.
My coworker, and local wizard, Bret Unbehagen used the trace logs to determine which tables the import wizard was using to store its index operation information. He then created the query below to produce a list of indexes that it was trying to recreate as well as generate a drop statement for each of those.
select BaseTableName, i.Name, 'drop index ' + i.name + ' on ' + BaseTableName + ';' from EntityIndex i join EntityView v on (i.EntityId = v.EntityId) where i.RecreateIndex = 1 AND I.IsPrimaryKey = 0 AND I.NAME IN (SELECT NAME FROM SYS.indexes) order by name;
So, the basic workflow is 1) let the import wizard proceed until it fails at “Upgrade Indexes”, 2) run the script above against your organization database to list the indexes that it wants to rebuild, 3) use the generated drop statements to preemptively drop those indexes, 4) restart the import so that it continues were it left off (feature of 2013+).
In our experience, this allowed the import wizard to continue through the “Upgrade Indexes” section without deadlocking and proceed with the import. Hopefully it can help you achieve success as well. If you have any questions please feel free to comment. Also, if you’d like to see more from Bret his information is listed below.
Bret Unbehagen (Twitter: @dbaunbe; Web: dba.unbe.org)
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