JDBC drivers questions

Guys,

I have some doubts related to JDBC drivers...

1) Native-protocol pure Java driver: This kind of driver converts JDBC calls directly into the network protocol used by DBMSs...What it means by saying network protocol used by DBMS???

2) JDBC-Net pure Java driver: This driver translates JDBC calls into a DBMS-independent net protocol, which is then translated to a DBMS protocol by a server. This net server middleware is able to connect its pure Java clients to many different databases....so does it mean that we always need a server middleware when we use this driver??

3) Also with JDBC-ODBC bridge driver plus ODBC driver, why do we need ODBC binary code and database client code to be loaded on each clients machine??

Please help guys!

1) Native-protocol pure Java driver: This kind of driver converts JDBC calls directly into the network protocol used by DBMSs...What it means by saying network protocol used by DBMS???

It means whatever protocol the database engine uses to serve requests. That could be something like TCP/IP, but could be something proprietory.

2) JDBC-Net pure Java driver: This driver translates JDBC calls into a DBMS-independent net protocol, which is then translated to a DBMS protocol by a server. This net server middleware is able to connect its pure Java clients to many different databases....so does it mean that we always need a server middleware when we use this driver??

Yes, though this should be part of your database.

3) Also with JDBC-ODBC bridge driver plus ODBC driver, why do we need ODBC binary code and database client code to be loaded on each clients machine??

That's just how ODBC work I'm afraid. Something has to implement the ODBC standards, and that something must be resident on the client machine.