Done a little more research - TDP is crazily high  - understandable in a way - having 2 cpus stuck together will generate lots of waste heat even when run...

Snapshot from the SAN is very good if you have the IOPS available on the SAN to cover test use cases.  It can snapshot DW very fast, even multi-tb DW...

I denormalised some of the underlying tables - this resulted in a much simpler plan.   Lesson I learnt here is that SQL is great at handling our data most of...

I spotted that but the cardinality issue was consistent in each fast and slow query plan. I didn't expect it cause the deviance in performance especially as the data is...

Very lucky to be able to adjust the underlying data structure (Data warehouse) - by reducing the plan complexity this problem looks to have gone away. Definitely an odd one...

slow query

The 2 plans came via sp who - I've ran the query to get the actual plan see attached.

Plans attached.  I will explore extended events.   Good tip about SQL Sentry Plan Explorer.

I can't easily share the plans as there is sensitive data in column names.    We've pushed the plans through a diff tool and the only differences are changes in...

Do you mean create an SSH tunnel from network b to a and then run the 
AES_DECRYPT(crypt_str,key_str) in the linked server select?  
This will keep the decryption on the...

Thanks - I had to wait for a bit for the http error log to appear. 

Microsoft.ReportingServices.Portal.WebHost!reportserverwebapp!d6!10/20/2017-09:07:24:: e ERROR: [mgggtq10]: OData exception occurred: System.Net.WebException: Unable to connect to...

My public key will be used in MYSQL to encrypt the data.    Once I load the encrypted data to SQL Server I will use the private key to decrypt the...

Oh I think I found it :

SELECT Name, public_key
FROM sys.asymmetric_keys;


Do you think this public_key varbinary can be used with MYSQL?

I don't believe it's an issue with stats  -  they were updated last week.
I've noticed there is some blocking immediately before the query starts.  This blocking seems to correlate...

If there was blocking wouldn't I see that in the top 10 waits?   My second highest wait is LCK_M_SCH_S but when I click on it there is No significant...