Organizing the Data Source
Once a data source has been cleaned and is ready for analysis, it can be organized in Tableau Desktop’s Data pane. By default, a Tableau data source with multiple tables will group fields by the table they came from. Dimensions will be listed first, followed by measures for the first table, and then there will be the second table’s list of fields, and so on.
To switch from table organization to grouping by folders, open the Data pane menu using the carrot in the top right and select Group by Folder. If using a multi-tabled data source, the Data pane will switch to a single list of fields, with dimensions above measures as opposed to table-specific lists. If the data source is a single table, then Group by Folder will be selected by default. Folder information is retained when switching between the Group by Folder and table views.
To create a folder, select the field that should be grouped within it, then right-click one of the fields...