When connecting to BigQuery from Tableau, you will want to take advantage of BigQuery’s ability to process large datasets and only bring results across the network. You should default into setting your Tableau connection against BigQuery as “Live” unless you have a specific reason to extract the data.

For an overview of what some of those reasons might be, read this excellent post by Tableau Zen Master, Jonathan Drummey where he outlines several use cases where extracts provide benefit . There is one important point to make about data extracts – they are not a replacement for data that might be in Google BigQuery, rather a complement. While they can be used to collect and aggregate data over time (i.e. incrementally add data according to a periodic cycle) this should be used as a tactical, rather than long term, solution. Incremental updates do not support update or delete actions to records that have already been processed – changing these requires a full reload of the extract.

With this live connection, you may also want to consider turning off automatic updates. When building a dashboard, as you place fields on a shelf, Tableau generates the view by automatically querying the data source. If you are creating a dense data view, the queries might be time consuming and significantly degrade system performance. In this case, you can instruct Tableau to turn off queries while you build the view. You can then turn queries back on when you are ready to see the result.