Description : A Column is having many repeated values which type of index you should create on this column, if you have to?
Last Answer : For example, assume there is a motor vehicle database with numerous low-cardinality columns such as car_color, car_make, car_model, and car_year. Each column contains less than 100 distinct values by themselves, and a b tree index would be fairly useless in a database of 20 million vehicles.