The way to achieve this is to use Custom Objects i.e. firstly create attributes for the dimension for example Company Code, Country etc. Now create a Custom Objects with dropdown i.e. 

customObjects: 

 - id: DIMENSIONS

  displayName: Dimensions

  customAttributes:

   columns:

    - id: company_code

    - id: country_name

The id reflected above is the attributes id, also make sure you are creating attributes in the same record.

Once you use the custom object in the dropdown you can update a variable with id, wherever you need to change the dimension of olap table use Record.${updated_variable}

I hope this helps!

got it, thanks