Error: "Lost connection to MySQL server during query" When Refreshing a Data Source on Tableau Online

Published: 26 Jul 2017
Last Modified Date: 17 Aug 2018


When attempting to refresh a data source on Tableau Online, the following message occurs:

"[MySQL][ODBC 5.3(w) Driver][mysqld-5.6.27]Lost connection to MySQL server during query."


  • Tableau Online
  • MySQL
  • SSL


Use one of the following workarounds: 

Option 1:

Use Tableau Bridge. For more information, see Publishers: Use Tableau Bridge to Keep Tableau Online Data Fresh.

Option 2:

  1. Download the data source.
  2. Open the extract in Tableau Desktop
  3. Go to the Edit data source tab.
  4. Click the arrow next to the data source name.
  5. Select Initial SQL.
  6. Enter the following: set net_write_timeout=7200
  7. Click OK.
  8. Republish the data source.


This behavior occurs due to an issue with the MySQL driver. Tableau is working to provide the MySQL development team with the necessary information to fix this issue. 

Additional Information

This issue typically occurs only with extracts greater than 10 million rows. 
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