SQL選擇最常見的值

Question

我很新的SQL（我正在使用MySQL），需要一些幫助。我目前正試圖從名爲PERSON的表中選擇最常見的年齡段。假設PERSON有具有值的AGE柱：10，10，20，20，30，該查詢應返回的值10和20

以下查詢只檢索頂部行（20）：

SELECT AGE FROM PERSON GROUP BY AGE ORDER BY COUNT(*) DESC LIMIT 1; 

我的另一個想法是嘗試類似：

SELECT AGE FROM PERSON GROUP BY AGE HAVING COUNT(AGE) = MAX(COUNT(AGE)); 

這將返回一個錯誤，指出它是無效使用組功能。

任何幫助將不勝感激。謝謝！

Answer 1

這樣做：

select age from persons 
group by age 
having count(*) = (
    select count(*) from persons 
    group by age 
    order by count(*) desc 
    limit 1) 

Answer 2

SELECT *, COUNT(AGE) as age_count 
FROM PERSON 
GROUP BY AGE 
ORDER BY age_count DESC 
LIMIT 1 

不能在這裏測試，但它應該工作。

Answer 3

WITH x AS (
    SELECT age, COUNT(*) numOfAge 
    FROM person 
    GROUP BY age 
) 
SELECT age 
    FROM x 
    WHERE numOfAge = (SELECT MAX(numOfAge) FROM x) 
    ORDER BY age