RLS (Row Level Security) in Tableau means restricting the data rows which a certain user can see from the Tableau workbook. RLS is different from Tableau permissions and it is used to control the access to content as well as feature functionality. For a better understanding of the difference between them, consider an example like in Tableau permission control whether a user can comment on a particular workbook or worksheet while in RLS it allows two users can see the same dashboards but only for the data that they are allowed to see.
The basic RLS workflow is as follows:
1. The user is identified by login into Tableau server or Tableau online
2. Then create a set of data entitlements for the user so that he can retrieved data from all possible data entitlements
3. Now the data is filtered by the entitlement for that user
4. For building the content, use published or filtered data for that generally calculated fields are used.
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