Error "Session Ended by Server" when Opening View

Published: 03 May 2013
Last Modified Date: 07 Jan 2019


When you try to open a view, a long spinner appears, followed by the error:
Session Ended by Server
An unexpected error occurred on the server. If you continue to receive this error please contact your Tableau Server Administrator.
Would you like to reset the view?

The following errors also appear in the log files:
Session1: StatementExecute: sess_guid=1 stmt_guid=30 
Session1: StatementExecute: FAILED, error=HashGrouping::InsertHash: collisions = <xxxxx>, size = <xxxxxxxx>, rate = 0.01
--- TDE Error -------------------------------------------------------------- 
File: db\DataEngineProtocol.cpp, Line: 2244 
Status: 4 
HashGrouping::InsertHash: collisions = <xxxxx>, size = <xxxxxxxx>, rate = 0.01 


  • Tableau Desktop
  • Tableau Server
  • Data extracts


To avoid this issue: 
  • Hide any unnecessary fields and re-create the extract. For more information, see Test Your Data and Use Extracts.
  • Filter or aggregate the view to reduce complexity and the number of rendered marks. For more information, see the Disaggregating and Aggregating Data article.
  • Split large, complicated workbooks into multiple, smaller and simpler workbooks to improve performance and reduce overall complexity.


This error can be caused by the following sequence of actions:
  1. Creating a data extract of a small data source in Tableau Desktop.
  2. Publishing the workbook to Tableau Server.
  3. Refreshing the original data extract that now uses a very large data set in Tableau Server.
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