What Is A SQL Server Big Data Cluster?

What Is A SQL Server Big Data Cluster?

SQL Server Big Data Clusters (BDCs) are a highly anticipated feature of SQL Server 2019, but what are they - and how can their capabilities best be leveraged? Let's dig a little deeper and find out. When SQL Server 2017 added support for Linux, the groundwork was laid for integrating SQL Server with Spark, HDFS, and other big data tools which are typically Linux-based. Big Data Clusters in SQL Server 2019 delivers on these integration possibilities and allows for both relational data and big data to be easily combined and analyzed. Big Data Clusters leverage enhancements to PolyBase in SQL…
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Finding Your Isolation Level

Finding Your Isolation Level

Often when I am troubleshooting SQL Server or Azure SQL Database performance issues which I believe to be related to concurrency, I get curious about what isolation level is being used. But how does one find out the isolation level a query is executing with? There are actually several locations that may need to be checked. Isolation Level Hierarchy Isolation level settings can be configured in three different places: Database (this is only a default, with limited choices)Connection (affects all queries using this connection)Statement (affects only a specific query) Database Isolation Levels Isolation level settings for the entire database exist…
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Topics I’d love to see at Conferences

Topics I’d love to see at Conferences

The Call for Speakers for PASS Summit 2019 has just closed, and now the Program Committee will begin the task of evaluating speakers and sessions and using those results to build a schedule. It's not easy. Really, it's not. I've served on the Program Committee numerous times and there's a lot of effort that goes into building that schedule. There are also many difficult decisions made, and many great sessions that there just isn't a timeslot for because they were pre-empted by an even better or more timely topic. These unfortunate facts got me thinking about topics that will probably…
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Dropping Offline Databases? Be Careful!

Dropping Offline Databases? Be Careful!

Well, maybe the title is a little bit harsh. You absolutely can drop a SQL Server database that's offline, but remember that its files won't be deleted if you do. Safely Dropping Databases At a previous employer, we had a well-defined process when dropping databases for a client. It went something like this: Confirm in writing the databases on which servers/instances to be dropped Take a final full backup of databases Take databases offline Wait at least two weeks to make sure nothing breaks in the absence of this database Drop databases This is a pretty good and safe method.…
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New Data Set: Chicago Parking Tickets

New Data Set: Chicago Parking Tickets

I'm always looking for new and interesting data sets for demonstration purposes. I enjoy using data that people can relate to - not only is it easily understood, but often it can be entertaining as well. This data set of real-world parking tickets does all that. A few weeks ago I came across this blog post by Matt Chapman. Matt filed FOIA requests with the City of Chicago and, after multiple attempts, was able to get access to over 36 million parking tickets written between 2003 and 2016. Matt goes on to explain Chicago's parking ticket database, how he processed…
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