The SQL Engine tab allows you to specify additional data source settings. The fields are optional unless otherwise noted. On this tab, provide values for the options in the following tables; then, click Apply.

Figure 1. SQL Engine tab

The SQL Engine tab of the ODBC Apache Cassandra Driver Setup dialog box

The SQL engine can be run in one of two modes: direct mode or server mode. When set to direct mode, both the driver and its SQL engine run in the ODBC application's address space. Some applications may experience problems loading the JVM because the process exceeds the available heap space. To avoid this issue, you can configure the driver to operate in server mode. Server mode allows the driver to connect to an SQL engine JVM running as a separate service.

By default, the driver is set to 0 - Auto. In this setting, the SQL engine attempts to run in server mode first, but will failover to direct mode if server mode is unavailable. If you prefer that the SQL engine runs exclusively in a particular mode, set the SQL Engine Mode option to 1 – Server to run only in server mode or 2 – Direct to run only in direct mode.

Table 1. SQL Engine tab Connection Options
Connection Options: SQL Engine Default
SQL Engine Mode If set to 0 - Auto, the SQL engine attempts to run in server mode first; however, if server mode is unavailable, it runs in direct mode.

If set to 1 - Server, the SQL engine runs in server mode. The SQL engine operates in a separate process from the driver within its own JVM. If the SQL engine is unavailable, the connection will fail.

If set to 2 - Direct, the SQL engine runs in direct mode. The driver and its SQL engine run in a single process within the same JVM.

Important: When the SQL engine is configured to run in server mode (0-Auto | 1-Server), you must start the SQL engine service before using the driver (see "Starting the SQL engine server" for more information). Multiple drivers on different clients can use the same service.
Important: Changes you make to the server mode configuration affect all DSNs sharing the service.

Default: 0 - Auto
JVM Arguments A string that contains the arguments that are passed to the JVM that the driver is starting. The location of the JVM must be specified on the driver library path. Values that include special characters or spaces must be enclosed in curly braces { } when used in a connection string.

Default:

For the 32-bit driver: -Xmx256m

For the 64-bit driver: -Xmx1024m
JVM Classpath Specifies the CLASSPATH for the Java Virtual Machine (JVM) used by the driver. The CLASSPATH is the search string the JVM uses to locate the Java jar files the driver needs.

Separate multiple jar files by a semi-colon on Windows platforms and by a colon on all other platforms. CLASSPATH values with multiple jar files must be enclosed in curly braces { } when used in a connection string.

Note: If no value is specified, the driver automatically detects the CLASSPATHs for all ODBC drivers installed on your machine.

Default: Empty String

When set to 0 - Auto or 1 – Server, additional configuration settings that are specific to server mode are exposed in the setup dialog. The settings for server mode are read only in the Driver Setup Dialog. For a description of these settings, see the table below.

To define the settings for server mode, click Edit Server Settings from the SQL Engine tab. The SQL Engine Service Setup dialog box appears.

CAUTION: Modifying the Server Settings will affect all DSNs using this service.
Note: You must be an administrator to modify the server mode settings. Otherwise, the Edit Server Settings button does not appear on the SQL Engine tab.

You use the SQL Engine Service Setup dialog box to configure server mode and to start or stop the service. See "Configuring server mode" for detailed information.

Table 2. Server Mode Configuration Options
Configuration Options: SQL Engine Service Description
Server Port Number Specifies a valid port on which the SQL engine listens for requests from the driver.

Default:

For the 32-bit driver: 19934

For the 64-bit driver: 19933
Java Path Specifies fully qualified path to the JVM executable that you want to use to run the SQL engine server. The path must not contain double quotation marks.

Default: The fully qualified path to the JVM executable (java.exe)

If you finished configuring your driver, proceed to Step 6 in "Data source configuration through a GUI." Optionally, you can further configure your driver by clicking on the following tabs. The following sections provide details for the fields specific to each configuration tab:

  • General tab allows you to configure options that are required for creating a data source.
  • Advanced tab allows you to configure advanced behavior.
  • Schema Map tab allows you to configure mapping behavior.
  • Security tab allows you to configure security settings.