I am using the toLabel function in an aggregate query, but it doesn't return the translation of the picklist value. 

I have changed the language of the user to Dutch and executed the following query:

    SELECT toLabel(Equipment__r.technical_Platform__c) FROM Maintenance_Schedule__c GROUP BY Equipment__r.technical_Platform__c 
The query returns the English value:  `Other Elevator likes`

When I remove the GROUP BY from the query, it returns the translated value:

    SELECT toLabel(Equipment__r.technical_Platform__c) FROM Maintenance_Schedule__c
Result with the Dutch value: `Overige`

I am not able to add the toLabel function in the GROUP BY, since only date aggregate functions are allowed as grouping expressions. I checked the documentation of the toLabel function, but it doesn't mention anything about grouping expressions. [Documentation][1] 

I also found a topic about the same issue on the developer forums of Salesforce, but it didn't get any replies and it is from 2012. [Topic][2]

I could execute a 2nd query without the GROUP BY to get the translated values and map it to results of the results of the query with the GROUP BY, but I am wondering if there is a better solution?


  [1]: https://developer.salesforce.com/docs/atlas.en-us.soql_sosl.meta/soql_sosl/sforce_api_calls_soql_select_tolabel.htm "Documentation"
  [2]: https://developer.salesforce.com/forums/ForumsMain?id=906F000000091NGIAY