Filters : Error "must be implemented"

when i apply $column.filter( $column == “test” ) in custom dimension, cube throws Error “must be implemented”. I am using the script as per the documentation, any inputs here? Thanks

Hello,

If you want to always filter the data cube by a certain dimension value, you can use the Subset Filter Formula ($column == “test”) under the Advanced part of Edit Data Cube. If you want to have the ability to remove the filter, just drag it to the Filter bar in the cube, click it and select the value.

Best,

Caroline