SQL Server 2017 – Interleaved Execution

I worked on testing interleaved execution with Microsoft back in January, I didn’t do much, just tested the functionality against some in-house code we had. (If you need a detailed primer on the subject, please see https://blogs.msdn.microsoft.com/sqlserverstorageengine/2017/04/19/introducing-interleaved-execution-for-multi-statement-table-valued-functions/)

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Azure SQL Database Compatibility Levels

Let’s start off with a quick overview of SQL Server versions and compatibility levels.

  • 100 = SQL Server 2008 and Azure SQL Database
  • 110 = SQL Server 2012 and Azure SQL Database
  • 120 = SQL Server 2014 and Azure SQL Database
  • 130 = SQL Server 2016 and Azure SQL Database
  • 140 = SQL Server 2017 and Azure SQL Database

So with SQL Server 2017 now available to the public what level is a newly created Azure SQL Database set at?

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SQL Server Phantom Reads

With Halloween around the corner what better topic to discuss than phantom reads. A phantom read occurs when rows have been inserted after a read operation and becomes visible in a follow-up read operation within the same transaction.

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SQL Server Tracking Tempdb Size

Here is a quick Extended Events script I knocked up where I wanted to track Tempdb file size changes for both the data and log file. I wanted to know who caused the tempdb growth, when it was done, what the T-SQL was and what sizes were involved. Not exactly complicated but hopefully useful.

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SQL Server Tracking Suspect Pages

Did you know that SQL Server tracks suspect pages and puts the details into the msdb database in a table called suspect_pages? Well it does, but the question I want answering is what happens if the page within the suspect pages table is fixed? Does it automatically get removed/updated or do we as the administrators have to do anything manually?

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DBCC CHECKDB Azure SQL Database

Who should be running DBCC CHECKDB for Azure SQL Database? Should it be Microsoft or should customers be scheduling it? All official information just tells you that you CAN run it (below shows the green tick) but still no clarity around the question.

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