Securing the Cube - Expert Cube Development with SSAS Multidimensional Models - page 249

If we have set up Writeback on our cube, we can also control whether the Role can
write data back to the cube by granting the Read/Write permission instead. Last of
all, if we want members of the role to be able to run Drillthrough queries and create
local cubes, we can grant permission to do this by choosing the appropriate option
from the Local Cube/Drillthrough Access drop-down box.
Cell security
Cell security is configured using three MDX expressions returning Boolean values.
They are Enable read permissions , Enable read-contingent permissions , and
Enable read/write permissions , as you can see in the following screenshot: