type 3 drive

[Simon Xu]

hi,
I was told that there are four types of drives. When do we use type 3? Thanks

[Joe McGuire]

Type 1 drivers are "bridge" drivers. They use another technology such as ODBC to communicate with a database.
Type 2 drivers use a native API to communicate with a database system. Java native methods are used to invoke the API functions that perform database operations.
Type 3 drivers do not require any native binary code on the client and does not need any client installation. These drivers use a networking protocol and middleware to communicate with a server. The server then translates the protocol to DBMS specific function calls. There are several networking options available to you when using Type 3 drivers, such as HTTP tunneling and pass-through servers.
Type 4 drivers are all Java drivers, so there is no client installation or configuration. A Type 4 driver uses Java to implement a proprietary DBMS vendor networking protocol.
[This message has been edited by Joe McGuire (edited June 13, 2001).]

[vaibhav punekar]

Does it mean that though TYPE3 and TYPE4 are generic in the sense client does not have to make much changes,affect the performance particularly speed as it goes through series of interfaces?Or is it that these issues are handled by the servers
such as Weblogic.

[rani bedi]

Type 3 driver is server-based, so there is no need for any vendor database library to be present on client machines. Further, there are many opportunities to optimize portability, performance, and scalability. Moreover, the net protocol can be designed to make the client JDBC driver very small and fast to load. Additionally, a type 3 driver typically provides support for features such as caching (connections, query results, and so on), load balancing, and advanced system administration such as logging and auditing.
Type 3 drivers require database-specific coding to be done in the middle tier. Additionally, traversing the recordset may take longer, since the data comes through the backend server