About Jdbc - MACROMEDIA COLFUSION MX 7 - CONFIGURING AND ADMINISTERING COLDFUSION MX Manual

About JDBC

JDBC is a Java Application Programming Interface (API) that you use to execute SQL statements.
JDBC enables an application, such as ColdFusion MX 7, to interact with a variety of database
management systems (DBMSs), without using interfaces that are database- and platform-specific.
The following table describes the four types of JDBC drivers:
Type Name
1 JDBC-ODBC
bridge
2 Native-API/partly
Java driver
3 JDBC-Net pure
Java driver
4 Native-
protocol/all-Java
driver
JDBC drivers are stored in JAR files. For example, the JDBC drivers that are supplied with
ColdFusion MX are in the macromedia_drivers.jar file. If you are using another JDBC driver, you
must store it in the ColdFusion classpath. For example, cf_root/cfusion/lib (server configuration)
or cf_webapp_root/WEB-INF/cfusion/lib (multiserver or J2EE configuration).
44 Chapter 3: Data Source Management
Description
Translates JDBC calls to ODBC calls, and sends them to the ODBC
driver.
Advantages Allows access to many different databases.
Disadvantages The ODBC driver, and possibly the client database
libraries, must reside on the ColdFusion server computer. Performance
is slower than other JDBC driver types.
Macromedia does not recommend this driver type unless your
application requires DBMS-specific features.
Converts JDBC calls to database-specific calls.
Advantages Better performance than Type 1 driver.
Disadvantages The vendor's client database libraries must reside on
the same computer as ColdFusion.
ColdFusion MX includes a type 2 driver for use with Microsoft Access
Unicode databases.
Translates JDBC calls to the middle-tier server, which then translates
the request to the database-specific native-connectivity interface.
Advantages No need for vendor's database libraries to be present on
client computer. Can be tailored for small size (faster loading).
Disadvantages Database-specific code must be executed in the
middle tier.
ColdFusion MX includes an ODBC socket type 3 driver for use with
Microsoft Access databases and ODBC data sources.
Converts JDBC calls to the network protocol used directly by the
database.
Advantages Fast performance. No special software needed on the
computer on which you run ColdFusion MX.
Disadvantages Many of these protocols are proprietary, requiring a
different driver for each database.
ColdFusion MX includes type 4 drivers for many popular DBMSs;
however, not all DBMSs are supported in ColdFusion MX Standard
Edition.