This is the best. Raita is basically yogurt with vegetables in. Usually. Anyway.
1 lb. yogurt; 1/2 a slicing cucumber or 1 small one; salt and pepper to taste.
Peel and grate the cucumber into a bowl. Add the yogurt, salt and pepper. Mix well. Chill.
If you water it down a bit (raita is ideally a bit thick) you can even have it as “soup” on a hot day. With a nice salad.