Voice of the DBA

Tag: SQLNewBlogger

  • Backup Log to Nul– #SQLNewBlogger

    Another post for me that is simple and hopefully serves as an example for people trying to get blogging as #SQLNewBloggers. This is also a part of a basic series on git and how to use it.

    There are times when you might be working on your demo/lab system and you generate a lot of tranasaction log activity. This isn’t data you want to save, so perhaps you want to remove the activity without saving it.

    There are a few choices:

    1. Run a normal log backup to a file, then delete the .trn file.
    2. Switch to simple mode
    3. Run a log backup to nul

    The first one is easy, but it’s a pain. I have to go to explorer, or open a VM, delete the file once I find it. The second one is what I’d suggest. In fact, as soon as you install SQL on a lab system, set model to Simple.

    The third item is valid, and I ran across this recently. When you use this syntax, make sure you use “nul” and not “null”. We are trying to send to /dev/nul, which is nowhere. If you backup here, then nothing happens. You can use this command:

    BACKUP Log sandbox2 TO DISK = N’nul’

    This will run a backup, and discard all of the backup data. When I say discard, I mean it’s not written anywhere.

    However, this is a real backup. It’s marked as such. This breaks a log chain, and you can do this with a full database backup as well, which means you really need another full backup after this to reestablish a baseline.

    Again, I ran across this, but it’s not what you want to do. If you need to clear the log, use

    ALTER DATABASE xx SET RECOVERY SIMPLE

    ALTER DATABASE xx SET RECOVERY FULL

    and take a full backup.

    More thoughts from Gail Shaw.

  • FizzBuzz–#SQLNewBlogger

    Another post for me that is simple and hopefully serves as an example for people trying to get blogging as #SQLNewBloggers. This is also a part of a basic series on git and how to use it.

    There’s been a programmer test that was used for awhile to see if a simple program could be constructed. It’s FizzBuzz, after a kids game, and designed to see if someone knows some logical program construction.

    The test is to produce a list from 1 to 100 and for multiples of 3, write “Fizz”, multiples of 5 produce “Buzz” and multiples of both produce “FizzBuzz”. This means you get:

    2017-07-06 10_18_44-SQLQuery1.sql - (local)_SQL2016.WideWorldImporters-RR (PLATO_Steve (64))_ - Micr

    It’s a simple test, but I wonder how long it would take you to write it in T-SQL? It took me about 2 minutes.

    Give yourself a little quiz today. For a challenge, also produce this in PoSh or some other language. I took about 5 minutes in PoSh, mostly because I had to look up some syntax.

    In case you think this doesn’t matter, I agree with Jeff Atwood. I’d like to look at someone’s code before I interview them for development. They should have some public code, maybe something they recommend.

    SQLNewBlogger

    If you’re looking for a blog topic, show us you can write this code.

  • DevOps Basics–Git log

    Another post for me that is simple and hopefully serves as an example for people trying to get blogging as #SQLNewBloggers. This is also a part of a basic series on git and how to use it.

    In a few previous posts I’ve looked at getting going with git, and in this post we continue by looking at how we can get some information about the actions we’ve taken.

    If we want to see what has happened in our repo, lots of clients will show a list of changes, but from the command line we use a simple “git log”. When I do this, I see the reverse chronological view of commits.

    2017-07-05 11_21_52-cmd - git log

    There are a lot of options for the log command, but there are a few I use often.

    Limit Entries

    I often use a –n, where n is a number, to limit what’s returned. For example, I’ll use –3 to show the last 3 commits.

    2017-07-05 11_27_17-cmd

    I also like the –p option, which will show differences. As you can see here, I added the UserRoles.SQL file, putting in new lines.

    2017-07-05 11_28_53-cmd - git log -3 -p

    At times, I like the –decorate option, which lets me know which branch was affected. This is helpful if I’m moving around on branches and I get confused. That does happen.

    2017-07-05 11_32_29-cmd - git log -4 --decorate

    There are lots of search options, and I use them at times, but rarely, so I’m usually searching for the documentation to know the dates or patterns. I do look at the –committer= syntax with my name. That lets me find my changes among others.

    I also like to keep things small, so using the –pretty=oneline option is handy.

    2017-07-05 11_36_04-cmd

    Now I can easily see what I’ve done lately.

    There are lots of ways to look at history, and certainly a client makes things easier, but I’d say that you should learn the command line, just in case there’s some issue and your client doesn’t display it properly.

    Last thing, when you run git log and end up with a colon prompt, you’re in the less utility (I think, been a long time since Unix). To get out just type:

    q

  • PowerShell $env Variables

    I was playing with containers the other day, reading a Simple Talk article on the topic, and noticed the code in PowerShell (PoSh) used the $env:xx syntax for variables. I know I’ve seen this before, but for some reason this struck me as something I knew little about.

    I decided to search a bit. One of the first links was from WindowsITPro, and they had some great code: Get-ChildItem ENV:. When I run that, I get lots of information:

    2017-06-14 14_59_52-powershell

    There are more items, but there are some interesting ones that I think could be useful for me, especially with automation. I have a OneDrive path, my home path, the Username, and more.

    I know I’ll never remember most of these, but really I just need to remember one: Get-ChildItem ENV: