基於MySQL中狀態列的最小數字更新列？

Question

我想更新與狀態數2 = 8

UPDATE tqueue 
SET status = '8' 
WHERE (SELECT MIN(number) 
     FROM tqueue 
     WHERE STATUS IN ('4') 
     AND get_ticket >= CURDATE() 
     AND get_ticket < DATE_ADD(CURDATE(), INTERVAL 1 DAY) 
     GROUP BY service) 

輸出：

-------------------------------------------------- 
number | status | get_ticket 
-------------------------------------------------- 
    3   4   2017-02-18 13:43:01 
    2   4   2017-02-18 12:34:03 
    1   8   2017-02-18 10:04:59 

Answer 1

您是否在尋找更新的status=8分鐘number到status=4？

試試這個：

SELECT @mynumber:=number FROM tqueue 
WHERE STATUS = '4' 
AND get_ticket >= CURDATE() 
AND get_ticket < DATE_ADD(CURDATE() , INTERVAL 1 DAY) 
GROUP BY service 
order by number asc 
limit 0,1 ; 

UPDATE tqueue SET status = '8' where number = @mynumber ; 

此外，您還可以使用臨時表更新自我參照：

CREATE TEMPORARY TABLE mytbl_numbers AS 
SELECT number FROM tqueue 
WHERE STATUS = '4' 
AND get_ticket >= CURDATE() 
AND get_ticket < DATE_ADD(CURDATE() , INTERVAL 1 DAY) 
GROUP BY service 
order by number asc 
limit 0,1 ; 

UPDATE tqueue SET status = '8' where number in (SELECT * FROM mytbl_numbers) ; 

更多有用的答案可以在[+] & [+] & ......

找到