JDBC Type 4 Driver Programmer's Reference for SQL/MX Release 3.1 (H06.23+, J06.12+)

Class.forName("com.tandem.t4jdbc.SQLMXDriver")
Adds the Type 4 driver class to the java.lang.System property jdbc.drivers property within the application:
jdbc.drivers=com.tandem.t4jdbc.SQLMXDriver
Establishing the Connection
The DriverManager.getConnection method accepts a string containing a Type 4 driver URL. The JDBC URL for the Type 4 driver is:
jdbc:t4sqlmx://ip_address|machine_name:port_number/[:][property=value [;property2=value2]...]
where
ip_address:port_number specifies the location where the NonStop MXCS association server is running.
property=value and property2=value2; specify a Type 4 driver property name-property value pair. The pairs must be
separated by a semicolon (;). For example,
T4LogLevel=ALL;T4LogFile=temp1.log
For information about the properties file, see Type 4 Driver Properties.
To establish a connection, the JDBC application can use the following code:
Class.forName("com.tandem.t4jdbc.SQLMXDriver"); //loads the driver
String url = “jdbc:t4sqlmx://ip_address|machine_name:port_number/”
Connection con = DriverManager.getConnection(url, “userID”, “Passwd”);
The variable con represents a connection to the MXCS data source that can be used to create and execute SQL statements.
Guidelines for Connections Using the Driver Manager
The Type 4 driver defines a set of properties that you can use to configure the driver. For detailed information about these properties, see
the Type 4 Driver Properties chapter.
Java applications can specify the properties in the following ways (listed in the order of precedence):
1. Using the
java.util.Properties parameter in the getConnection method of DriverManager class.
2. Using the database URL in the
DriverManager.getconnection method, where the URL is:
jdbc:t4sqlmx: //ip_addr|machine_name:port_num/property=value
3. Using a properties file for the JDBC driver. The properties file is passed as a command-line parameter. The format to enter the
properties file in the command line is:
-Dt4sqlmx.properties=location-of-the-properties-file-on-disk
For example, -Dt4sqlmx.properties=C:\temp\t4props
For information about the properties file, see Creating and Using a Properties File in the Type 4 Driver Properties chapter.
4. Using JDBC properties with the -D option in the command line. If used, this option applies to all JDBC connections using the
DriverManager within the Java application. The format in the command line is:
-Dt4sqlmx.property_name=property_value
For example, -Dt4sqlmx.maxStatements=1024
Stored Procedures
Java applications can use the JDBC standard CallableStatement interface to run stored procedures (SPJs) by using the CALL statement. For
more information, see the SQL/MX Guide to Stored Procedures in Java.
The following SPJ features are not supported:
executeBatch for callableStatements
setXXX() methods with parameter names instead of parameter numbers
The feature of SPJ returning a
java.sql.ResultSet is available from T1249V20^ABT. This feature is available only from ODBC/MX SERVICES
and ODBC/MX SERVER, compliant with SQL/MX
3.0 or later versions.
Connection Pooling
The Type 4 driver provides an implementation of connection pooling, where a cache of physical database connections are assigned to a client
session and reused for the database activity. If connection pooling is active, connections are not physically closed. The connection is returned to
its connection pool when the
Connection.close() method is called. The next time a connection is requested by the client, the driver will return