Tableau Postgres Connector Throws "Error 0x4F2352E8" When VARCHAR Columns or Spatial Types Exceed Memory Limits
Published: 19 Mar 2021 Last Modified Date: 08 Jul 2022
The Tableau Postgres connector displays the following errorwhile reading query results:
Tableau Desktop 2020.4.4 and later
Tableau Server 2020.4.4 and later
You will need to reduce the fetch size by using a TDC file.
See the .xml code example below. Adjust the fetch-size-custom value to suit your needs. Smaller values will use less memory, but will increase the time to retrieve the results. The acceptable value that can be customized using TDC is between 1 and 5000. The suggested value for spatial types:10 The suggested value for other type:100
To a single datasource in Tableau Desktop or Prep Desktop.
The fetch size is saved in the datasource after publishing, if the TDC file is applied. This is the recommended way, so that the reduced fetch size doesn’t slow down all datasources.
Install the TDC in My Tableau Repository/Datasources.
You will have to download the datasource and re-publish from a Desktop product with the .tdc applied. Once the .tdc is applied you may want to remove it, so that the reduced fetch size no longer applies to their datasources.
Install in their folder, for example My Tableau Prep Repository/Datasources Ensure that the filename ends in .tdc, for example: postgres.tdc
This error is caused when a single block of rows, a single fetch, exceeds the memory limits. This usually occurs with long VARCHAR columns or spatial types.
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