Ability to create derived values/columns in table/pivot views

It would be extremely useful to be able to create a derived values/columns in table/pivot views that would take some other values (e.g., two other columns) and calculate some expression. That calculated value can then be used for sorting or charting.

Ideally, some simple subset of SQL would be allowed, which would cover both arithmetics, but also would allow to call into various math/string functions.

Start by examining the existing table and pivot views and how their values are used for sorting and charting. Define the supported expression and SQL-function scope, then consider the feature complete when derived values can be calculated from other columns and consumed by both sorting and charting.

Written by the indexing model from the issue text.