Be yourself, if you really have given interview by yourself than you should not be worried as they will be asking similar questions. Prepare to answer the query related questions about how you would test using query(ETL).
I don't think you should be worried at all. Never show your nervous face, try to smile and answer what you know and if you try to answer something you don't know say you have Knowledge but no deep exp otherwise they will dig in that same questions. by the way is this your first job?

Hope this help !!!