Live or Extract
When you connect to a file or a server, on the data source workplace, in the top-right corner, you have the option to use a Live or Extract connection, as you can see in the following screenshot:
There is a big difference between these two options, so let's look at them in detail.
Live
A Live connection creates a direct link between the Tableau data source and your data (server or file). It means that, if the data changes, you see the impact in Tableau directly after actualizing the data source, or when you reopen the workbook.
The problem with a Live connection is that you are dependent on the performance of the database. Large text files, big Excel files, or an unoptimized database can be very slow to analyze in Tableau. Also, if you are connected to an online database, you are dependent on the internet connection, and you won't be able to work offline. Every time you use a field from your data source, Tableau sends a query to the database, meaning that if there...