20751-12 Rev.5 1-3
Architecture
In a Netezza appliance two-tier client-server system, the data source is stored on the
Netezza appliance, which handles all database access processing. The ODBC driver on the
client system uses a network connection to a Postgres process running on the Netezza
appliance host, which coordinates SQL statement processing functions.
JDBC
The JDBC architecture consists of four major components:
Java Application. The application, written in the Java programming language, is
responsible for interacting with the user and for invoking JDBC API functions. These
API functions submit SQL statements for processing by a file system or a database
management system. The Java application uses interfaces, classes, and methods,
defined by the Java API, to connect to and access a data source.
Java Virtual Machine. When a Java application is compiled, the Java object program
consists of byte codes. The Java virtual machine is responsible for converting the Java
byte codes into instructions capable of being executed on the machine on which the
application is running. The Java virtual machine functions as an intermediary between
the Java object program and the machine on which the application is running. There is
a different Java virtual machine implementation for each platform. The Java virtual
machine makes it possible for the same Java program to be run, without changing or
recompiling, on any machine for which a Java virtual machine has been implemented.
JDBC Driver. The JDBC driver processes the JDBC API interfaces, classes, and methods
in the Java application. The Java application uses the JDBC driver to interact with the
file system or database management system to access the required data. It also returns
results to the Java Virtual Machine, which, in turn, returns those results to the Java
Application. There is a different JDBC driver for each vendor’s DBMS or data source
type. Netezza provides a JDBC driver for Version 3.0 of the Oracle JDBC API specifica-
tion. The driver is a Type 4, pure-Java driver that Netezza has tested for conformance
with the Oracle JDBC specifications on Windows, Linux, and UNIX platforms. The
Netezza JDBC driver supports all NZSQL data types, includes password encryption, and
provides for connection options for host, port, and database. Starting with Netezza
appliance Release 4.6, the JDBC driver requires Java release 1.5 and later.
Data Source. A Data Source contains the sets of data the JDBC driver accesses, along
with all the environments associated with the data. These environments might include
file access or database access software, an operating system, and a networking
platform.
To use JDBC to access a Netezza appliance, you need at least a two-tier client-server con-
figuration, as shown in the example in Figure 1-2.
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