KNOWLEDGE BASE

Extract Creation from Oracle Table Slow to Complete


Published: 09 Mar 2015
Last Modified Date: 07 Sep 2016

Issue

When creating an extract from an Oracle database, it might take a long time to complete and the following message might appear in Tableau Desktop's log files:

OCIWrapper::ORAResults::ORAResults Out of memory when allocating [10000] rows, defaulting to [1] row

Environment

  • Tableau Desktop 8.1.11 and later versions
  • Oracle

Resolution

  • If using 32-bit Tableau Desktop, upgrade to 64-bit Tableau Desktop, which is able to use more system memory for processing. See Upgrading Tableau Desktop for more information.
  • Hide or exclude large memory-intense database fields such as varchar(4000) from the extract, or change data types at the database level.
  • Ensure that the preferred Oracle driver from the Driver's Page has been installed on the workstation. 

Cause

When connecting to an Oracle table with many rows of large sized data types, instead of allocating more memory than is available and failing entirely, Tableau Desktop may bind and fetch one row at a time at the expense of performance.
Did this article resolve the issue?