Sql-Server

As a standard practise for IaaS and on-premises SQL Servers, I usually like to install Ola Hallengren’s maintenance scripts. Why invent the wheel when we already have a super-shiny one? These scripts include integrity checks, which run DBCC CHECKDB. Is DBCC CHECKDB needed anymore? It depends. 😉 It comes down to a cost/benefit analysis. I have been working with Sql Managed Instances quite closely over the past couple of years and wondered whether DBCC CHECKDB needs to be run on these. The whole point of CHECKDB is to notify us that something is wrong but also to do something if the database becomes corrupt in some way. They are very IO intensive operations which can impact user queries on the server. ...

Should we stop using -- in SQL comments? Interesting blog post from Brent Ozar on whether we should stop using -- for SQL Comments. I use these comments a lot because they are quick and easy for me to type. I don’t like voluminous comments but this is a good point. If clicking the link is too much effort for you, he is saying you should do this SELECT * FROM dbo.Users WHERE DisplayName = N'Brent Ozar' /* This line is a comment */ AND Location = N'Iceland' ORDER BY Reputation DESC; instead of this ...

On a client site recently a question was asked about the file share witness in a SQL Server failover cluster on-premises, and where to put it if you only have two sites. As always, it depends! Let’s look at some scenarios. Bear in mind that use of the Azure Cloud Witness requires Windows Server 2016 or later. Topology 1 Three node cluster with 2 nodes at primary and 1 at disaster recovery (DR) Most people want high availability at their “primary site” and are happy to have standalone capability at the business continuity (DR) site. To save storage costs, I would recommend a SQL Server failover clustered instance so you only have one set of storage at the primary site. On top of that you can place an availability group in asynchronous mode to a standalone server at your DR site. In this configuration there are several scenarios to consider, and they can all be served with a file share witness at the primary site, or use a cloud witness in azure. ...

You run performance tests as well as functional tests when deploying new code changes to SQL Server, right? Not many people do, I think you should, and this article will show you how to do it by harnessing an existing performance tool, rather than writing your own monitoring infrastructure from scratch. Any good performance monitoring tool that records information to a database will do fine, and we prefer to use Sentry One. ...

In February 2018, myself and Paul Anderton gave a presentation on how to correlate database deployments with performance issues within the context of a DevOps pipeline. We used Sentry One as our monitoring tool in a Performance Test environment so that we could catch badly performing deployments before they got to production and caused havoc. If you would like to see the recorded video, then you can download it from here: http://info.sentryone.com/partner-webinar-performance-problems ...

Azure Container Instances are still in Preview and not officially available for Windows yet, which made me smile. It took me a while to figure out how to get this working so I thought I’d share what I’ve found. Containers are great for lightweight testing of code before deployment to production servers because they can be created so quickly and they give the same environment to test in very reliably. Now that Microsoft is offering container instances in Azure it means you don’t have to worry about provisioning and configuring your own docker host/cluster. The options for deploying SQL Server are really getting large now, look at this list below! ...

Why use Windows Containers? When creating database applications we need consistency in all our environments to ensure quality releases. Traditionally developers might have their own instance of SQL Server on their workstation to develop against. Database projects would be created in SSDT and pushed to source control when ready for testing. If you’re not using SSDT for database development already, then you should seriously consider it to make your life easier and increase the quality of your releases. Ed Elliot explains why in this blog post. ...

As part of automation of database and application deployments, it makes sense to be able to create new SQL Server instances quickly and with minimal resources. I have already explored containers and written about it on this blog, but I’d like to turn your attention to setting up SQL Server on Windows Server Core for those of you that run SQL Server on-premise or within VMs in the cloud. In a domain environment it should be pretty simple to just create a PowerShell session to your target Windows Server where your account is a local administrator and then simply run setup at the command line to install SQL Server, right? ...

How to move a replication subscriber to a new server with no downtime to the publisher? In a recent data centre migration for a client we had a problem where we needed to move a subscriber to a new data centre without incurring any downtime to the publisher or loss of data after the subscription migration. The application was sending hundreds of transactions per second to the publisher. An additional complication was an upgrade to SQL Server 2016 from SQL Server 2008 R2 on the subscriber. ...

Is SQL Server in a container faster than a VM? I briefly looked at SQL Server containers when Windows Server 2016 was released. Containers offer the ability for rapid provisioning, and denser utilization of hardware because the container shares the base OS’s kernel. There is not a need for a Hyper-Visor layer in between. As a recap for those that are not up speed with containers, the traditional architecture of databases in a VM is like so: ...