handling multiple queries with the same connection

[satya sxy]

Hello someone,
I am trying to use java servlets and jdbc for a project i am working on. I have a register servlet that does the registration part. When i submit this servlet,it should first check the database table if the username already exists ,if it exists then it do nothing. in case if the submitted username doesnt exist then the submitted information should be inserted into the database table. I tried doing this but i get erorrs. could someone throw light on this topic as to how to handle both the select query and insert query one after the other.
Any help, ideas, suggested readings are appreciated.
thanks,
shailu.

[Jamie Robertson]

algorithm:
connect
query the table for the username
if username does not exist
write to the database

//connect to the database using Connection con = ....
String user;
//set the user string to username to be checked
PreparedStatement ps=null;
ResultSet rs=null;
ps = con.prepareStatement("SELECT username FROM table1 where username = ?)");
ps.setString(1, user);
rs = ps.executeQuery();
if (!rs.next())
{
//no match was found
ps = con.prepareStatement("INSERT INTO table1 (username, password, whatever) VALUES (?,?,?)");
ps.setString(1, user);
ps.setString(2, "password");
ps.setString(3, "whatever");
ps.executeUpdate() 
}

I didn't compile the above code, but it should give you a start. As you can see, I prefer PreparedStatements over Statements in any situation that I can!
Jamie

[satya sxy]

Thanks jamie,
i will try this one.
I appreciate your help. thanks a lot.
shailu