2013-04-09 106 views
0

我有一个包含文章记录的表。现在我想计算源文章之间的平均时间,所以我可以自动增加或减少我的抓取时间间隔。如果我在两个日期之间从一个源中选择记录,那么用MySQL Query可以吗?记录之间的平均时间MySQL

表布局:

id | title | description | create_date   | source_id 
----------------------------------------------------------------- 
1 | Title 1 | A description | 2013-04-09 21:38:00 | 5 
2 | Title 2 | A description | 2013-04-09 22:16:00 | 5 
3 | Title 3 | A description | 2013-04-09 23:54:00 | 5 

结果应该是:

diff between 1 and 3 = 136 min 
----------------------------- 
Average is 45,33 minutes (crawler interval: 2720 seconds) 

我也能做到这一点在PHP中,如果这是更好!

+0

试试这个: http://stackoverflow.com/questions/2237159/get-average-time-between-times-in-sql 或本: http://stackoverflow.com/questions/2237159/get-average-time-between-times-in-sql 干杯:) – mCube 2013-04-09 21:10:32

回答

2

是的。

SELECT 
    UNIX_TIMESTAMP(MAX(create_time)) - UNIX_TIMESTAMP(MIN(create_time))/COUNT(*) AS 'avg' 
FROM table 
WHERE source_id = 5 
    AND create_time BETWEEN '2013-04-01 00:00:00' AND NOW()