@User For what sort of tests? If we're talking unit tests, it makes sense to hand-craft the input data. On the other hand, for end-to-end pipeline tests, consider using a data mocker to generate fake data (if you have stuff like data security restrictions), or simply subsampling your source data. Note that creating test data can be a pretty big challenge in and of itself, depending on how many tables you need to mock and how realistic it needs to be.