Sun Microsystems JDBC/ODBC Adapter manual Type I JDBC-ODBC Bridge, Type One Driver

Chapter 1	Section 1.1
Introducing the JDBC/ODBC eWay	About Java Database Connectivity (JDBC)

database and middleware vendors. The various driver types are described in the following sections:

ƒ“Type I: JDBC-ODBC Bridge” on page 8

ƒ“Type II: Partial Java driver” on page 9

ƒ“Pure Java driver for database middleware” on page 10

ƒ“Type Four Driver: Direct-to-database pure Java driver” on page 11

Type I: JDBC-ODBC Bridge

This combination provides JDBC access via ODBC drivers. ODBC binary code--and in many cases, database client code--must be loaded on each client machine that uses a JDBC-ODBC Bridge. A product called SequeLink from Data Direct Technologies provides a driver that supports some ODBC drivers (for example Microsoft Access).

Type one drivers provide JDBC access via one or more Open Database Connectivity (ODBC) drivers. ODBC, which predates JDBC, is widely used by developers to connect to databases in a non-Java environment.

Pros: A good approach for learning JDBC. May be useful for companies that already have ODBC drivers installed on each client machine — typically the case for Windows- based machines running productivity applications. May be the only way to gain access to some low-end desktop databases.

Cons: Not for large-scale applications. Performance suffers because there's some overhead associated with the translation work to go from JDBC to ODBC. Doesn't support all the features of Java. User is limited by the functionality of the underlying ODBC driver.

Type One Driver

A JDBC/ODBC bridge provides JDBC API access through one or more ODBC drivers. Some ODBC native code and in many cases native database client code must be loaded on each client machine that uses this type of driver.

Figure 1 Typical Type 1 Driver Configuration

JDBC/ODBC eWay Adapter User’s Guide 8 Sun Microsystems, Inc.