除了我喜欢的范围表以外,单行答案可能是:
SELECt SUM(IF(age < 20,1,0)) as 'Under 20', SUM(IF(age BETWEEN 20 and 29,1,0)) as '20 - 29', SUM(IF(age BETWEEN 30 and 39,1,0)) as '30 - 39', SUM(IF(age BETWEEN 40 and 49,1,0)) as '40 - 49',...etc.FROM inquiries;

除了我喜欢的范围表以外,单行答案可能是:
SELECt SUM(IF(age < 20,1,0)) as 'Under 20', SUM(IF(age BETWEEN 20 and 29,1,0)) as '20 - 29', SUM(IF(age BETWEEN 30 and 39,1,0)) as '30 - 39', SUM(IF(age BETWEEN 40 and 49,1,0)) as '40 - 49',...etc.FROM inquiries;