如何计算出生日期的年龄，并将每个成员分组到sql的年龄范围内

I have an sql table that stores people's details i.e id, name, DoB, registration_date and address. I would like to calculate the age of each individual and then group them into these ranges: 20-30, 31-50, 51 & over.I have an sql table that stores people's detail