TYPO ALERT!!! I left out the all important word INTERVAL. The query should read:
SELECT accesstime FROM userlog where accesstime > (NOW() - INTERVAL 15 minutes) and IP='10.1.7.205' LIMIT 1; Sorry all! -S [EMAIL PROTECTED] wrote on 03/29/2005 02:50:35 PM: > Graham Anderson <[EMAIL PROTECTED]> wrote on 03/29/2005 02:20:48 PM: > > > I am trying to determine the average time that a Distinct IP address is > > using the server > > > > > > If I have 15 thousand records of ip addresses and access times like: > > > > IP Now() media.id > > -------------------------------------------------------------- > > 10.1.7.205 20050329121645 67 > > 68.252.32.76 20050329095923 72 > > > > > > And, I want to set the cut-off time to 15 minutes... > > Basically, if the user has not requested media on the server in last 15 > > minutes, the user has logged off.... > > > > > > can someone point me in the right direction as I am very new to more > > advanced mysql queries > > > > many thanks > > > > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > > > Since you didn't post your actual table structure, I will have to make up > some information (like table and field names). I am also assuming that you > store your access time in a datetime field and that your server is v4.1 or > newer. > > SELECT accesstime > FROM userlog > where accesstime > (NOW() - 15 minutes) > and IP='10.1.7.205' > LIMIT 1; > > If you get a record, the user is still active; No record = too late. Not > only does this use the same clock that you used to create the other > entries (the one on the MySQL server) but it avoids the use of MAX() or > ORDER BY (both of which will slow you down) and it will use an index if > you have one. > > If this doesn't work for you, tell us why and we can work towards a > solution. > > Shawn Green > Database Administrator > Unimin Corporation - Spruce Pine
