如何計算mysql查詢中的行數？

Question

我想根據行號查詢mysql嗎？假設我想查詢最後10行，如何在mysql查詢中做到這一點？

這裏是我的MySQL查詢，但根據6天的間隔查詢，但我需要根據最後10行的代6-天的間隔進行查詢，

SELECT people_id, people_number 'people number', count(people_number) 'Occurs', 
    (
    Select count(people_number) from people_history 
    where people_id = 5486 and date > DATE_SUB(NOW(), INTERVAL 6 DAY) 
) 'Total', 
    count(people_number)/(
     Select count(people_number) from people_history 
     where people_id = 5486 and date > DATE_SUB(NOW(), INTERVAL 6 DAY) 
)*100 'Percent' 
FROM people_history 
where people_id = 5486 and date > DATE_SUB(NOW(), INTERVAL 6 DAY) 
group by people_id, people_number 
order by Percent desc` 

Answer 1

讓您的查詢這樣的：

SELECT * FROM people_history ORDER BY id DESC LIMIT 10 

Limit可以限制的結果你從查詢得到的金額。通過按ID排序，您可以獲取表格中的最後20個結果。

Answer 2

LIMIT：

SELECT 
    people_id, 
    people_number 'people number', 
    count(people_number) 'Occurs', 
    (Select 
     count(people_number) 
    from 
     people_history 
    where 
     people_id = 5486 
     and date > DATE_SUB(NOW(), INTERVAL 6 DAY)) 'Total',    
    count(people_number)/
     (Select 
      count(people_number) 
     from 
      people_history 
     where 
      people_id = 5486 
      and date > DATE_SUB(NOW(), INTERVAL 6 DAY)) *100 'Percent' 
FROM 
    people_history 
WHERE 
    people_id = 5486 
    and date > DATE_SUB(NOW(), INTERVAL 6 DAY) 
GROUP BY 
    people_id, people_number 
ORDER BY 
    Percent desc 
LIMIT 0, 10 

你可能想重寫一下這個查詢。

Answer 3

well「last」必須引用某種排序（order by ....）語句。你總是由10

Answer 4

反向您的訂單，所以最後10是第10位，該限制將制約的結果數返回。它在查詢的最後。看看documentation for SELECT，然後轉到LIMIT部分。

對於您的查詢，如果您在最後加上LIMIT 10，您將只能得到您要查找的10個結果。將LIMIT和ORDER BY（ASC或DESC）結合起來得到第一個或最後一個結果。

Answer 5

LIMIT加限制N（N你的情況= 10）