JDBC Type 4 Driver 1.1 Programmer's Reference

Illustrates the three layers of the Type 4 driver—the API layer, IDL layer, and the Transport layer— to the MXCS association
server
Data Sources
JDBC Data Source (client-side)
MXCS Data Source (server-side)
The term data source logically refers to a database or other data storage entity. In this manual, two concepts of data source
concepts apply:
A JDBC (client) data source, which is physically a Java object that contains properties such as the URL of the physical
database, the catalog to use when to this database, and the schema to use when to this database. The JDBC data source
also contains methods for obtaining a JDBC connection to the underlying database.
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An MXCS (server) data source, which is physically a set of information that is created and managed by MXCS. This
data source contains configuration information, which defines the semantics of MXCS servers created with that server
data source.
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JDBC Data Source (client-side)
All JDBC data source classes implement either the javax.sql.DataSource interface or the
javax.sql.ConnectionPoolDataSource interface. The Type 4 driver data source classes are
com.tandem.t4jdbc.SQLMXDataSource and com.tandem.t4jdbc.SQLMXDataSource. (These classes are
defined by the JDBC 3.0 specification.)
Typically, a user or system administrator use a tool to create a data source, and then register the data source by using a JNDI
service provider. At run time, a user application typically retrieves the data source through JNDI, and uses the data source’s
methods to establish a connection to the underlying database.
A DataSource object maps to an instance of a database. In the Type 4 driver product, the DataSource object acts as an
interface between the application code and the database and enables connection with an MXCS data source.
MXCS Data Source (server-side)
Server data sources reside on a NonStop server. Each server data source represents a pool of SQL MXCS servers that share the
same NonStop SQL context. A server data source is typically created by a NonStop system administrator, who defines the
semantics of all connections made through that server data source. For example, the server data source contains information on
how many MXCS servers can be in its corresponding pool and how many connections can be handled through this data source.
Security
Clients connect to the MXCS server with a valid Guardian user name and ID, using standard JDBC 3.0 APIs. An application
can make multiple connections to MXCS using different user IDs, and creating different connection objects.
The Type 4 driver provides for user name and password authentication before to MXCS. The password is encrypted with a
proprietary algorithm provided by the MXCS product.