Fetching Data from server using volley?

This may be dumb question as a Beginner am really confused am using volley for fetching json data into my recyclerview and need to store it into sqlite now my doubt is i can fetch and bind the data to recycler view and also i stored the value into sqlite database but as soon as i switch activity again its fetching from server and saving it into my sqlite database getting double double value how to resolve this issue can someone give me the tips !! Only new data should get save into sqlite db how can i do this!! can you guys please share some idea!!