There are five types of JDBC drivers in use:
Type 1: JDBC-ODBC bridge
Type 2: partial Java driver
Type 3: pure Java driver for database middleware
Type 4: pure Java driver for direct-to-database
Type 5: highly-functional drivers with superior performance
For most applications, the best choice is a pure Java driver, either Type 3, Type 4, or even Type 5.
Type 5 drivers (such as DataDirect Connect for JDBC drivers) offer advanced functionality and superior performance over other driver types.
Type 4 Drivers are the most common and are designed for a particular vendor's database.
In contrast, a Type 3 driver is a single JDBC driver used to access a middleware server, which, in turn, makes the relevant calls to the database. A good example of Type 3 JDBC driver is the DataDirect SequeLink for JDBC driver.
Type 1 drivers are used for testing JDBC applications against an ODBC data source. Type 2 drivers require a native database API to be used. Both Type 1 and Type 2 mix a Java-based API with another API.
The following figure shows a side-by-side comparison of the implementation of each JDBC driver type. All four implementations show a Java application or applet using the JDBC API to communicate through the JDBC Driver Manager with a specific JDBC driver.
