Driver Configuration Options for Linux and Mac OS X

The configuration options that you can use to control the behavior of the MapR ODBC Driver for Impala are listed and described in the table below.

Note: You can set configuration options in your odbc.ini and mapr.impalaodbc.ini files. Configuration options set in the mapr.impalaodbc.ini file apply to all connections, whereas configuration options set in an odbc.ini file are specific to a connection. Configuration options set in odbc.ini take precedence over configuration options set in mapr.impalaodbc.ini.

Key Default Value Default
AuthMech 0

You can use the following authentication mechanism values:

  • 0 – No Authentication
  • 1 – Kerberos
  • 2 – User Name
  • 3 – User Name and Password
  • 4 – User Name and Password (SSL)
  • 5 – No Authentication (SSL)
CAIssuedCertNamesMismatch 0

Whether to allow the common name of a CA-issued SSL certificate to mismatch the host name of the Impala server. The following values are possible:

  • 0 – Do not allow the names to mismatch.
  • 1 – Allow the names to mismatch.

Note: This setting is only applicable to the User Name and Password (SSL) and No Authentication (SSL) authentication mechanisms. It is ignored by other authentication mechanisms.

Driver   The location of the MapR ODBC Driver for Impala shared object file.
HOST   The IP address or hostname of the Impala server.
KrbFQDN   The fully qualified domain name of the Impala host used.
KrbRealm   If there is no default realm configured or if the realm of the Impala host is different from the default realm for your Kerberos setup, use this option to define the realm of the Impala host.
KrbServiceName   The Kerberos service principal name of the Impala server.
PORT 10000 The listening port for the service.
PWD   The password of a user account on the host that is running Impala. PWD is required if AuthMech is set to User Name and Password or User Name and Password (SSL).
RowsFetchedPerBlock 10000 The maximum number of rows that a query returns at a time. Any positive 32-bit integer is a valid value, but testing has shown that performance gains are marginal beyond the default value of 10000 rows.
SocketTimeout 0 The number of seconds after which Impala closes the connection with the client application if the connection is idle.
TrustedCerts

For 32 bit driver:

/opt/mapr/ impalaodbc/lib/32/
              cacerts.pem 

For 64 bit driver:

/opt/mapr/ impalaodbc/lib/64/
                cacerts.pem

Used to specify the location of the file containing trusted CA certificates for authenticating the Impala server when using SSL.

If this setting is not set, then the driver defaults to using the trusted CA certificates file installed by the driver.

Note: This setting is only applicable to User Name and Password (SSL) and No Authentication (SSL) authentication mechanisms, and it is ignored by other authentication mechanisms.

TSaslTransportBufSize 1000

The number of bytes to reserve in memory for buffering unencrypted data from the network.

Note: In most circumstances, the default value of 1000 bytes is optimal.

UID anonymous The user name of an existing account on the host that is running Impala. UID is required if AuthMech is set to User Name and Password or User Name and Password (SSL). UID is optional if AuthMech is set to User Name.
UseNativeQuery 0

By default, the driver transforms the queries emitted by an application to convert the queries into an equivalent form in Impala SQL. Use this option to specify whether or not the driver transforms queries. The following values are possible:

  • 0 – Transform the queries into Impala SQL.
  • 1 – Do not transform the queries (use the native query instead).

Note: If the application is Impala-aware and already emits Impala SQL, then set this option to 1 to avoid the extra overhead of query transformation.