Re: WELCOME to php-db@lists.php.net
| From: | Jeff Hibser | Date: | Wed, 24 Apr 2002 19:09:01 +0000 |
| Subject: | Re: WELCOME to php-db@lists.php.net | ||
| Groups: | php.db | ||
| Request: | Send a blank email to php-db+get-18786@lists.php.net to get a copy of this message | ||
Hello,
I am relatively new to php, and have a question regarding polling a
mysql database and defining groups of data:
Say I have a table that looks like this:
Time | Speed
--------------------
1016278580 | 0
1016278582 | 0
1016278584 | 0
1016278586 | 3
1016278588 | 7
1016278590 | 5
1016278592 | 4
1016278594 | 0
1016278596 | 0
1016278598 | 2
1016278600 | 0
Now, the time is epoch time. Speed is MPH (so 0 means I am stopped).
What I want to do is make a call into mysql that will return to me when
I stopped, and for how long. IE:
You stop at 1016278580 for 6 seconds (calculated until speed !=0).
You also stopped at 1016278594 for 4 seconds
You also stopped at 1016278600 , and are still stopped (or something
like that)
Whats the best way to do this? I can query the database for every row
where speed = 0, but how do I make the distinction between the groups
of 0's (IE, in the example above I would essentially have
three "groups" of zeros that I would need to identify). Is there
someway to pull the data out of mysql in this format (Select * WHERE
speed=0 UNTIL speed !=0)? Something like that? Or would this be better
handled by PHP after pulling the data out of mysql?
Any help I can get on this would be greatly appreciated.
Thanks.
-Jeff