Rabbit-In-a-Hat can generate a framework for creating a set of unit tests. The framework consists of a set of R functions tailored to the source and target schema in your ETL. These functions can then be used to define the unit tests.

These are the steps to perform unit testing:

1. Create the testing framework for your source and target database schemas.
2. Using the framework in R, define a set of unit tests
3. Use the framework to generate testing data in the source data schema
4. Run your ETL on the test data to produce data in the CDM schema
5. Use the framework to evaluate whether the CDM data meets the defined expectations

It is advised to use R-Studio for defining your unit tests. One reason is that RStudio will automatically prompt you with possible function and argument names after you've only typed the first few characters.

In Rabbit-in-a-Hat, have your ETL specifications open. The source data schema should be loaded from the White-Rabbit scan report, and the target data schema should be selected (usually the OMOP CDM v5). Go to File → Generate ETL Test Framework, and use a file name with the .R extension, for example MyTestFrameWork.R.

Next, create an empty R script, and start by sourcing the R file that was just created:

source("MyTestFrameWork.R")

Be sure to run this command to