Hi, Jaqueline!

Have you tried Build Restriction field of the cube?

Build Restriction is in the properties of the cube.

Put there SQL Expression which goes after WHERE clause. It will filter the facts which will be included to your cube. E.g. if you base your cube on Samples.Person you can set the Cube Build Restriction as:

NAME='John' 

to limit the facts of the cubes to only records with 'John' in Name property.

HTH