An extract is a proprietary compressed data source created by Tableau Desktop. Since the 10.5 release, the file extension for an extract changed from the .tde to the .hyper format. Thus the new format makes use of the hyper engine, which was discussed in Chapter 1, Getting Up to Speed – A Review of the Basics. An extract can be stored locally and accessed by Tableau to render visualizations.
Consider the following points that make an extract file an excellent choice for improved performance:
- Extracts can be quickly generated at an aggregate level.
- See the walkthrough of the Extract Data dialog box below.
- Extracts are a columnar store.
- Relational databases typically store data using a Row Store methodology. A columnar store records as sequences of columns.
- In the following example, note that Row Store is excellent for returning individual...
