The filter that finds a group's rows again by one of its keys, as the engine returned it: Is Empty for an empty key; for a float, In of the value and the 32-bit float nearest it, written in full, since a 32-bit column's value comes back as its shortest text (0.02), which the database's widened value never equals, and Cube can't tell such a column by its type (PLAN §11.10); else the grid's 'Filter by' rule (buildQuickFilterRule), Equal on the value read as the column's type. undefined when the value can't be compared.