Shantanu Shukla You would choose a dataset based on the characteristics of the tests you want to perform. In a very general case, you can utilize the TPC-H (https://www.tpc.org/tpch/) benchmark datasets to begin your tests.
I will just agree with Mr. Sadha Shiva Reddy Chilukoori. You train your ANN on as much similar data to the testing set as you can, else the model will have high errors.