Unit Testing the Data Access Layer - Testing Update Methods? - sql

I'm looking into adding some unit tests for some classes in my data access layer and I'm looking at an update routine that has no return value. It simply updates a row based on the id you provide at whichever column name you provide.
Inside of this method, we collect the parameters and pass them to a helper routine which calls the stored procedure to update the table.
Is there a recommended approach for how to do unit testing in such a scenario? I'm having a hard time thinking of a test that wouldn't depend on other methods.

Test the method that reads the data from the database, first.
Then you can call the update function, and use the function that was tested above, to verify that the value that was updated is correct.
I tend to use other methods in my unit tests as long as I have tests that also test those that were called.
If your helper functions are in the database (stored procedures or functions) then just test those with a DatabaseUnitTest first, then test the visual basic code.

I would just use a lookup method to validate that the data was properly updated.
Yes, technically this would relay on the lookup method working properly, but I don't think you necessarily have to avoid that dependency. Just make sure the lookup method is tested as well.

I would use the method to get that data and check the return value to what you updated and Assert the expected value. This does assume the method used to retrieve the data has been tested and works correctly.

I use nhibernate and transactions and for unittests I don't commit to the database but I flush the session which gives the same errors if needed but doesn't write the data.
Of course if you have a build server you just run the unittests against a freshly made database which is freshly made on each build. Try using an filebased database like firebird or something.

Related

Is it possible to automate comparisons between database results with groovy script?

I am in the process of migrating an application which currently performs all of its SQL calls internally (as part of the code) to Restful services so that the SQL calls are handled externally. I am in need of a smart way to test that these changes have no effect on the actual data that is retrieved from the database.
I was thinking it might be possible to write some automation tests against the APIs and then use groovy script to compare the results of both.
Using Soap UI
1: old SQL call - returns XML
2: New Restful call -returns JSON
3: Compare both results.
The issue I have is that a direct call returns XML whereas the new call returns JSON.
I just need to know if this is a waste of time or if this is worth pursuing?
The only other option I can think of currently is to manually run two tests on both versions at the same time and observe any differences if they occur.
Thanks for taking the time to read.
If you need any more detail please let me know but tried to keep it brief!

How to build automation test for Webservice api that's independence with Database

I'm new with automation test term. Currently I had a project which would like to apply Cucumber to test Rest Api. But when i try to assert out put of endpoints of this api base on current data, so I wonder what happen if I changed environment or there are any change in test database in the future, so my test case will be potential to fail.
What is the best practice to write test which's independence on database.
Or I need to run my test with empty separated db and execute some script to initialize db before to run test?
In order for your tests to be trustworthy, they should not depend on the test data being in the database or not. You should be in control of that data. So in order to make it independent of the current state of the database: insert the expected data as a precondition (setup) of your test. (And delete it again at the end of the test). If the database connection is not actually part of your test, you could also stub or mock the result from the database (this will make your tests faster, as you're not using db connectivity).
If you are going to assert the response value that comes (eg:number of cars) it is actually impossible to make it database independent. I guess you can understand why? What I would do in a similar situation is something like this.
Use the API and get the number of cars in the database (eg: 544) and assign it to a variable.
Using the API add another car to the database.
Then again check the total cars in the database and assert (should be 544 + 1 else fail)
Hope this helps.

Single FakeApp for all test in Play Framework

I want to have single FakeApplication for all my test.
My final goal is to set up database and use it in all test. They should access single database and share data in it. I can not use H2, because I use some MySQL features(fulltest search, for example). But if there is no started application, I can't call "DB.withTransaction" because there is started application yet. But it should start once, because it drops all tables and create new ones.
How can I do it?
I am using scala and JUnit. I solved my problem next way: I just created singleton for my fake application, which is retrieved as an implicit val. So, all work about creating and cleaning database is done on first fetch.

How to access context after each Entity Framework db migration

When I Add-Migration, I get the appropriate DbMigration class with the Up / Down methods, where I am able to make schema changes and (with the use of the Sql() method) can make data/content changes as well.
I'd like to be able to make content changes per migration using the database context. I understand that I could use the Seed method in a Configuration class, but my understanding is that I can only wire up one Configuration with my initializer.
I'd prefer to have a UpCompleted()/DownCompleted() methods that would provide access to the db context after the migration completed. This would enable writing incremental data/context change "scripts" in a manner that would be less prone to errors than using the Sql() method.
Am I missing something? Is this possible?
Thanks!
That doesn't really work because the context only has your most recent model - which can only be used to access the database once the most recent migration has run (which is effectively what Seed achieves).
For an example of how this idea breaks, if you moved a property from one class to another then seed logic from older migrations would no longer compile. But you couldn't change it to use the new property because the corresponding column wouldn't exist in the database yet.
If you want to write this kind of seed/data-manipulation logic, you need to put it at the end of the Up/Down methods and use the Sql method to perform it using raw SQL.
~Rowan

Entity Framework Code First - Tests Overlapping Each Other

My integration tests are use a live DB that's generated using the EF initalizers. When I run the tests individually they run as expected. However when I run them all at once, I get a lot of failed tests.
I appear to have some overlapping going on. For example, I have two tests that use the same setup method. This setup method builds & populates the DB. Both tests perform the same test ACT which adds a handful of items to the DB (the same items), but what's unique is each test is looking for different calculations (instead of one big test that does a lot of things).
One way I could solve this is to do some trickery in the setup that creates a unique DB for each test that's run, that way everything stays isolated. However the EF initilization stuff isn't working when I do that because it is creating a new DB rather than dropping & replacing it iwth a new one (the latter triggers the seeding).
Ideas on how to address this? Seems like an organization of my tests... just not show how to best go about it and was looking for input. Really don't want to have to manually run each test.
Use test setup and tear down methods provided by your test framework and start transaction in test setup and rollback the transaction in test tear down (example for NUnit). You can even put setup and tear down method to the base class for all tests and each test will after that run in its own transaction which will rollback at the end of the test and put the database to its initial state.
Next to what Ladislav mentioned you can also use what's called a Delta Assertion.
For example, suppose you test adding a new Order to the SUT.
You could create a test that Asserts that there is exactly 1 Order in the database at the end of the test.
But you can also create a Delta Assertion by first checking how many Orders there are in the database at the start of the test method. Then after adding an Order to the SUT you test that there are NumberOfOrdersAtStart + 1 in the database.