Hi Geert Van Damme, Thanks for the reply. So, if I use DB connection pooling, writing to DB for each session is not something to worry about? Hmmm, still worries me, but I guess I can only try it out.
I've been working on DB connection pooling actually, will post another message again if I encounter any problem. Thanks, June > > One way I can think of is to map a servlet to the root(where the > index page is) and for each new session(not for each request for > index page, because I don't want to include those accesses made > by people who are already at the site) that gets created I > increment the visit count in the database. Same thing goes for > the shopping cart. However, I think this approach to write to > database each time is costly in terms of db access. > That's the way to do it. One important thing however is: Use DB Connection pooling !!!!! Without the overhead of creating a connection, how many inserts do you think you can do? Did you test it? Depending on hardware, OS, DBMS, server load .... it might range between 300 and 50.000 per second. (very rough figures, just my personal experience, YMMV) If you have a website that handles over 300 new visitors per second, or 300 shopping cards per second, you're a rich man ;-). In that case you can easily afford a whole server parjk and several developers. I see you're talking about 150 or 200 per day. IMO, I wouldn't care about your problem up till 500.000 hits per day. The first steps then are: - Buy bigger HW - Move the DB to a dedicated server - Load balance the app server. - Load balance (HW) the web server) - Sell your entire product and retire ;-) > Another way which I think is more desirable is to store those > counts in the servlet until the servlet gets destroyed. I guess > I can write to database in the destroy method and get the latest > count from database in the init method of the servlet. However, > since what I want is the daily counts, not just the sum of > everythings, how do I differentiate them and write yesterday's > count to yesterday's column and write today's count to today's > column, especially when I don't have control over when the > servlet is destroyed? > You do have control over it (unless the server crashes or something, so it's not 100% safe) But the most important thing is: don't try to optimize speed unless you did proper profiling! > Hang on, how about this? I declare a vector(since I don't know > how many Dates I will be storing until the servlet gets > destroyed) as an instance variable, in the doGet method I > instantiate a Date for each Session and compare it with the last > Date element in the vector. If it's the same date, I increment > the count that belongs to that Date, and if not, I add another > Date element with new count. In the destroy method, I write what > is in the vector to the database. In the init method, I get the > last date from db with the count and store it in the > vector......Would this work? Or is there an easier way? Am I > making something that is so easy compliated? Yes, you're making it way too complicated ;-) Make it work first, when you see you really need to aggregate the inserts (I doubt it) then rebuild your approach. There's a chance < 1/100 that you'll ever need to. Geert Van Damme http://messenger.yahoo.com.au - Yahoo! Messenger - A great way to communicate long-distance for FREE! =========================================================================== To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com
