LTAF is a functional automation framework, but if I understand you right, you can accomplish this in several ways:
1. Prep the database before test execution. Usually done at testcase constructor, you can populate database with test data.
2. If you use Inversion of Control or a ServiceLocator patterns to create a data repository, you can set up your IoC container or ServiceLocator during your test constructor and then run your app. If you are using LTAF with tests in the same website this is very simple because you can directly code against your application setup.
Hope it helps,
- Federico