Are You Using Version Control for Your Database or Are You Ticking a Box?

 

You use a version control system to solve certain problems, to accomplish certain tasks. These are:

• Keep track of who changes what, when and why.
  
• If necessary, use previous versions of the code base for testing, development etc…
  
• Move changes between environments faster, with fewer errors during deployment.
  
• Improve productivity of the team (i.e. less time coordinating manually and more time developing. For example different developers working on the same parts of the code base simultaneously and merging their changes at a later time, hopefully mostly automatically.).

If you are using a version control system but not accomplishing any of the things above, are you really using a version control system?

Here is a perfectly reasonable scenario that I’ve seen in the real world. I’ve seen this scenario with teams using Git with SQL Developer, SVN/Git with another Oracle PL/SQL IDE. Invariably, they all end up here:

1. In the DEV database, you make changes to the package PKG_HIRING in the HR schema and then commit the package under /HR/PKG_HIRING.sql file in Git.
   
2. Next, another developer makes changes to the same package. He commits his changes under /HR/next_version/PKG_HIRING.sql, because… why not? It’s not like there is any enforcement.
   
3. A third developer commits his changes to /HR/PKG_HIRING.pkb because for some reason, the tool he uses for editing uses the .pkb suffix for packages.
   
4. The fourth developer named John, decides to copy PKG_HIRING to a file and work on it. He thinks he can move his changes to the database later. So he creates /HR/JOHN_DO_NOT_TOUCH/PKG_HIRING.sql
   
5. A fifth developer, makes changes to the HR.PKG_HIRING package but forgets to commit the package to Git. Hey it happens…
   
6. A sixth developer makes even more changes. He commits the package to Git under HR/PKG_HIRING.sql thereby committing not only his changes but also the fifth developers changes.

Three months later, you are tasked with deploying the latest version of the HR application to the TEST database. Which PKG_HIRING package are you going to deploy to TEST?

I actually know the answer to this question. You will deploy the one in the HR schema. It’s the safest option. I cannot help but wonder tough.. in these past three months, did John save his changes to the database? If so, how did he do it? Did he simply overwrite the package? What if some changes were lost?

At this point, I have to ask… Why do you even have a version control system? Why does that Git/SVN repo even exist? Is it useful at all or are you just doing all this just to tick a box and to be able to say that you are using a version control system?

Gitora solves all these problems above. It creates a version control system around Git and enforces it at the database level.

Let’s repeat the same steps for the six developers but this time let them use Gitora:

1. In DEV, you make changes to the PKG_HIRING package in the HR schema. When you are done, you open the Gitora web app, you see the list of database objects you changed, you select the ones you want to commit (in this case PKG_HIRING) you add a comment to the commit (such as the ticket number) and click the commit button.
   
2. The second developer follows the same process as you. He cannot make any changes to the package until you are done with it. Once you are done, he can make his changes. He opens the Gitora App, commit his changes to Git and is done. Note that, he doesn’t get to choose which folder he saves the PKG_HIRING.sql file to. Gitora creates a well structured working directory with reasonable folder and file names for database objects. The locations of these files are also standard. When there is human decision involved with naming and putting files in the file system, a lot of errors can occur. Gitora prevents these errors.
   
3. The third developer’s IDE used the .pkb extension for his file. Since developers don’t get to name the files or choose the folders they save database object scripts to, the third developer also has no choice but to follow the same process as the first two developers. By the way, Gitora works with any IDE. You can use SQL Developer, SQL Navigator, TOAD or PL/SQL Developer. It doesn’t matter. Everyone in your team can use a different editor if they choose to do so. Gitora still works.
   
4. The fourth developer was impatient. He created a new file under JOHN_DO_NOT_TOUCH and saved his changes to that file. With Gitora, he has no direct access to Git and the Git working folder. (Gitora is a server side solution. You don’t install Git to developer’s computers.) So he cannot do that. However, if he wants to do mischief, he still can copy the PKG_HIRING package to a new file in his computer and make changes there. Then, he can simply overwrite everything in the PKG_HIRING package with his version at a later time. This will cause some changes to be lost in the package depending on when he does it. He can even go ahead and commit his changes to Gitora. But hold on a second. At some point, either during development or testing, the mistake he made will be detected. In the first scenario, there is no way to know for certain who erased all the functioning code and exactly what code should be put back to the package. It will be trivial to use Git to figure out who deleted the perfectly functioning code from PKG_HIRING because Gitora always keeps track of who changed what, when and why. Since we can know when the mistake happened, we will know the correct version of the package to put back to. John will take the heat for his egregious mistake and merge his changes to the correct version of the package. No one wants that kind of heat. It is easy to see that Gitora incentivizes the right kind of behavior among teammates by keeping everyone accountable for their actions as well as making it possible to recover from critical mistakes.
   
5. The fifth developer simply forgot to commit his changes to Git. With Gitora there are two ways this can be caught. First, the sixth developer who wants to edit the package will contact the fifth developer to ask when the package will be available. Second, Gitora web app always shows which objects are locked by whom. So before preparing a deployment, you can always check if there are any database objects that are locked.
   
6. In the first scenario, the sixth developer committed fifth developers changes along with his. With Gitora, the sixth developer will always commit only his changes because there is no way he can gain access to the PKG_HIRING without the fifth developer releasing the package first. Gitora enforces that if an object is being edited by someone, no one else can edit it. With Gitora, version control is not something you do on the side but it is tightly integrated into your workflow and enforced.

And finally, three months later, you are tasked with preparing the deployment to TEST. How are you going to move the changes to the TEST database? With Gitora, all you need to do is to open the Gitora app, connect to the TEST database and pull the HR repo from DEV to TEST and you are done.

Going back to the beginning of the article; Gitora makes Git a useful version control system for the Oracle Database.

As shown in the second scenario with Gitora you can:

• Keep track of who changes what, when and why.
  We caught John misbehaving.
  
• If necessary, use previous versions of the code base for testing, development etc…
  We recovered an old version of PKG_HIRING and have John merge his changes to it.
  
• Move changes between environments faster, with fewer errors during deployment.
  Done via point and click Gitora Web Application.
  
• Improve productivity of the team (i.e. less time coordinating manually and more time developing. For example different developers working on the same parts of the code base simultaneously and merging their changes at a later time, hopefully mostly automatically.).
  The second scenario reduced manual coordination significantly. Gitora can do a lot more. You can have different teams work on the same code base at the same time and merge their changes just like Java, JavaScript developers. However that’s beyond the scope of this article. Please read this article and this article to learn more about how you can implement parallel development with Gitora.