Voice of the DBA

Tag: syndicated

  • Sabbatical Decisions

    My employer, Red Gate Software, offers a sabbatical to their employees, and this year I’m taking mine. I’ll be gone from June 2 – July 14, away from work, but I’ll be blogging here about my experience.

    I wrote before that I had a sabbatical coming from Red Gate Software this year. It’s a fantastic perk, one that grants all employees 6 weeks of paid time off every five years. The time is supposed to help you grow in some way, not necessarily related to work.

    I had lots of comments on my piece, and I’ve thought about it quite a bit. With my schedule at home, and other items on the agenda, I’ve decided to do the following:

    1. Learn something
    2. Help someone
    3. Wander on my own with a project

    Those broad ideas boiled down into these actual physical items.

    1. Take a class at a local community college. I have an interest in woodworking and I’m looking to go through one of their summer classes. I’ve not made the time in the past, mostly because of the distance to travel to the school, but this is a good time to experiment with the idea.
    2. Volunteer with a charity part time. I have a soft spot in my heard for Habitat for Humanity, and I plan to volunteer with them in both their stores, and on some local builds.
    3. Make something with my hands. As I mentioned, I have an interest in woodworking, but I don’t always get the chance to work through a large project with so many other things happening at the ranch. I decided that I’ve wanted to build a flagpole, strictly for me, and that’s my project.

    Now that my surgery is done and I’m on the mend, I’ll be working through each of these, setting up the details and getting ready for time off.

    My sabbatical is scheduled for Jun 2-July 14, though I won’t be back right away as I will be heading to England right away for SQL Bits XII.

    The blog will likely switch from data topics and SQL Server to some progress on the sabbatical so you can follow along if you like. I won’t syndicate these posts over to SQLServerCentral, as they’re not really relevant, so if you’re interested in how it’s going, subscribe here or keep checking back.

  • Continuous Delivery Visualization

    A good one, one of the better diagrams I’ve seen.

    CD

    From http://markosrendell.wordpress.com/2014/03/03/practical-benefits-of-continuous-delivery/

    Now if we can get tooling and processes to make this work reliably for databases.

  • Speaking at Connections

    I just got my acceptance to the DevConnections, SQLConnections in September for two sessions:

    • Continuous Integration for Databases
    • Maintaining High Performance When Using Encryption

    I enjoy the Connections events, usually finding time to go check out an ASP.NET or developer session of some sort.

    Now’s the time to register and save. There will be some great pre-cons as well, including one from a scary individual that I know well.

  • The Cardinality Estimator in SQL Server 2014 – Going Forward and Backward

    I saw a talk from Joe Sack (b | t) on the cardinality estimator (CE) in SQL Server 2014 and found it very interesting. To be fair, some of the "how it works" isn’t something I care about much, but I did like Joe sharing some places in which you might find problems with your queries and how the cardinality estimator might affect you. The talk is worth seeing if you get the chance.

    However one of the really interesting things, and an item I appreciate Microsoft building, is a switch to turn off the new CE. Actually, it’s not turned off, but you can set it to pre-SQL Server 2014 behavior (essentially 2005-2012) or to SQL Server 2014 behavior. What’s even better is that you can set this in a number of ways.

    Setting Database Behavior for all Queries

    Turning on the new CE is as simple as setting the compatibility level to 120. This will turn on the new CE for your queries in this database.

    The flip side is setting your compatibility level to something below 120 (110, 100, etc.) and your queries will use the old CE behavior in the query optimizer.

    Setting Behavior for Queries

    You can also specifically test queries with either the new or old CE. The QUERYTRACEON option can be used with these two flags.

    • 9481 – Uses the 2012 (pre-2014) CE with queries. This is used when the database is in SQL Server 2014 (compatibility mode 120) mode.
    • 2312 – Uses the new 2014 CE when the database, or defaults, are set to use the 2012 CE.

    This is documented in KB 2801413 from Microsoft.

    Setting the Server Level

    There is a trace flag that you can use at Server startup that globally sets the CE behavior. Set 9481 at startup and your SQL Server 2014 databases will use the old CE by default. Joe documented this on his blog.

    Usage

    I think this is great because if you are concerned about workloads being effected by the CE changes, then you can set the old CE as the default and test on your real production server by executing specific queries with the new CE and the query plan.

    Alternatively, if you upgrade and find problems, you can duplicate the old CE by using a query hint and see if the query performs better.

    I’d like to see this upgrade/downgrade granularity in more features that can potentially affect performance and I would say this is a fantastic architectural win by the SQL Server development team.