Sun Microsystems eWay JDBC/ODBC Adapter - Manual (Page 8)

Chapter 1 Section 1.1
Introducing the JDBC/ODBC eWay About Java Database Connectivity (JDBC)
JDBC/ODBC eWay Adapter User’s Guide 8 Sun Microsystems, Inc.
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