2.10 - Overriding Session Properties - Teradata QueryGrid

Teradata® QueryGrid™ Installation and User Guide

prodname
Teradata QueryGrid
vrm_release
2.10
created_date
September 2019
category
Administration
Configuration
Installation
User Guide
featnum
B035-5991-099K
Designating a Spark SQL connector property as overridable in the QueryGrid portlet allows users to override configured Spark SQL connector properties when executing queries during an individual processing session.

For the Spark SQL initiator session, setSessionOverride() is used at the Foreign Server level to override configured Spark SQL connector properties. The session override applies to all non-native tables that belong to the Foreign Server.

  1. Under Fabric Configuration, select Fabrics.
  2. Select the fabric.
  3. Do one of the following:
    Option Description
    To override a Spark SQL connector property in the Connectors tab
    1. Click the Connectors tab.
    2. Click "" next to the connector that has a property you want to override.
    3. Select Edit.
    4. Click "" next to Connector Software.
    5. Find the Spark SQL connector property you want to override and click the Overridable check box.
    6. Click OK.
    7. Click Save.
    To override a Spark SQL connector property in the Links tab
    1. Click the Links tab.
    2. Click "" next to the link that has a property you want to override.
    3. Select Edit.
    4. Click "" next to Initiating Connector or Target Connector.
    5. Find the Spark SQL link property you want to override and click the Overridable check box.
    6. Click OK.
    7. Click Save.
  4. [Optional] To override the Spark SQL connector property during a Spark SQL session for Foreign Server s1, use the syntax in the following example.
    s1.setSessionOverride("linkBufferSize=100000, numExecutors=4, hadoopProperties=name1:value1 | name2:value2")
    When overriding hadoopProperties, you must use the pipe (|) symbol to split Hadoop properties and a colon (:) to split name value pairs, as shown in these examples.
    The following example is used to override hadoopProperties during a Teradata Session targeting a Hive connector:
    SET FOREIGN SERVER ATTR = 'servername=sparkserver1; hadoopproperties=name1:value1|name2:value2;' FOR SESSION VOLATILE
  5. [Optional] To clear Spark SQL connector property overrides without closing a Spark SQL session for Foreign Server S1, use the syntax in the following example.
    s1.setSessionOverride("")