Speeding up Tableau


Some of my worksheet queries that usually takes seconds are now running for minutes but not actually doing anything. Has something gone wrong? What can I do to get Tableau to speed up?


In your Tableau root folder, create a Tableau Datasource Customization (.tdc) file with the following content. The file extension must be .tdc, but the file name does not matter.

<?xml version='1.0' encoding='utf-8' ?>
<connection-customization class='redshift' enabled='true' version='8.0'>
	<vendor name='redshift' />
	<driver name='redshift' />
		<customization name='CAP_QUERY_WHERE_FALSE_METADATA' value='yes' />
		<customization name='CAP_SKIP_CONNECT_VALIDATION' value='yes' />
		<customization name='CAP_SUPPRESS_DISCOVERY_QUERIES' value='yes' />
		<customization name='CAP_CREATE_TEMP_TABLES' value='no' />
		<customization name='CAP_SELECT_INTO' value='no' />
		<customization name='odbc-connect-string-extras' value='UseDeclareFetch=0' />

The key line for our purposes is this one, which set the cursor to off: <customization name='odbc-connect-string-extras' value='UseDeclareFetch=0' />.

After you’ve created the .tdc file, grep the log.txt file to ensure the config is being loaded. You should notice that your queries load faster.

For more information about .tdc files and Redshift-Tableau connection customizations, see the following articles: