Question

The timestamp field is a DATETIME column in a format like 2012-03-19 00:23:14. How can I compare two rows of timestamps and find the larger one? The query below that I am using isn t working.

UPDATE report 1 status =  time is larger  WHERE EXISTS 
  (SELECT ip_src, layer4_sport, timestamp FROM  
      (SELECT ip_src, layer4_sport, timestamp from report 1) AS tmpb  
   WHERE  report 1.layer4_sport = tmpb.layer4_sport 
   AND report 1.ip_src = tmpb.ip_src  
   AND  report 1.timestamp > tmpb.timestamp 
   GROUP BY ip_src, layer4_sport,  timestamp HAVING COUNT(*) = 2)

Answer 1

亲爱的上帝,现在的问候就是科索沃。

失踪的人是SET的辛塔克斯,然后是小组的辛迪加人,应从EXISTS中删除。

UPDATE report 1 SET status =  time is larger  WHERE EXISTS 
  (SELECT ip_src, layer4_sport, timestamp FROM  
  (SELECT ip_src, layer4_sport, timestamp from report 1) AS tmpb  
   WHERE  report 1.layer4_sport = tmpb.layer4_sport 
   AND report 1.ip_src = tmpb.ip_src  
   AND  report 1.timestamp > tmpb.timestamp)

Answer 2

如果时间序列大于B时间stamp,你可以尝试使用声明来验证。

select if(UNIX_TIMESTAMP( 2009-02-01 00:00:00 ) > UNIX_TIMESTAMP( 2009-01-01 00:00:00 ), true, false)

Answer 3

try the UNIX_TIMESTAMP(), UNIX_TIMESTAMP(date) functions to compare two timestamps.

友情链接