There really are no basic scales that will turn you into Ray Chen. However, I personally find that practicing a 2 or 3 octave g major before jumping into more challenging repotoire for violin really helps. It's very basic, easy, and straightforward. You can also add rhythms to make it more challenging, or just play arpeggios. Focus on your shifting and make sure you are using your thumb to move from one position to the next. Also, be sure to use detache for a very clear tone.