sql - Calculate the time difference between two timestamps in mysql

Question

I work on a MySQL database table that has a column containing timestamps (Ex. 2014-09-16 09:08:05) of the time I ping different hosts. My question is how could I calculate in minutes the difference between the first ping and the last one for specific hosts? Also how could I specify different timestamps for the start and the end of the difference mentioned above (instead of the first and last ping). Here is an example of the table:

|--|---------|-------------------|----|
|id|http_code|pingtime           |host|
|--|---------|-------------------|----|
|10|200      |2014-09-16 09:08:05|2   |
|--|---------|-------------------|----|
|11|200      |2014-09-16 10:07:05|1   |
|--|---------|-------------------|----|
|12|200      |2014-09-16 10:14:10|2   |
|--|---------|-------------------|----|

I hope that I've explain myself clear enough.

Answer 1

You could use the native TIMESTAMPDIFF function :

SELECT TIMESTAMPDIFF(<INTERVAL>,<timestampFrom>,<timestampTo>);

If you want to find the difference between the first and the last timestamp of a given host ID, here you are:

SELECT TIMESTAMPDIFF(MINUTE,MIN(pingtime),MAX(pingtime))
FROM yourTable
WHERE host = 2;