🚀 go-pugleaf

"Sudesh" <sudeshc@vfemail.net> wrote in message 
news:47c38262@newsgroups.borland.com...

> let me give you a simple example. a quiz program.
> database and quiz application exe will reside on server and program will
> be accessed from a number of clients, say 300. Concurrent read (for
> accessing questions)and write (saving marks at the end of quiz time)
> operation will be required.
> any tips for this?

If you are not concerned about security then you can go with a simple 
client/server model.  All clients would have direct access to the database 
tables and would be able to read and write as needed.  This might become 
problematic if you have some adventursome students that write custom 
applications to look at the table structure and adjust their answers (or 
hack the answers of others).

If you are concerned with security then depending on the database you can 
configure each user to be able to only perform certain tasks like inserting 
records on particular tables (the quiz answers table, for example).  Or, if 
that's not possible you could also take a 3 tier approach where you write a 
server application that resides on the database server (or at least on the 
same side of the firewall) that serves questions to the clients and reads 
answers from the clients.  You will need to look into how to write 
TCP/Client and TCP/Server apps using Indy or other tools to complete this 
task.

> which is the best and fastest database? MS Access is ok?

MS Access is okay for multiple concurrent reads but I have read that it does 
not work very well for multiple concurrent writes.  I don't have the details 
I just remember this being a problem for a lot of people in the past.  A 
better choice is SQL Server.  You can also go with MySQL, Oracle Lite, SQL 
Server Express, etc.  Some may have nominal fees depending on your uses.

Note, if you go with the 3-tier approach MS Access will work fine since you 
can serialize all access to the database behind-the-scene.

Clayton