I do have in my project model 3 datasets showing stores (DS_SITE), cities (Cidades) and weather (DS_DADOS_CLIMA) like in the image below:
And I want to see the name of the store with it's respectively weather information, but when I try select the store name to the report, it's not permitted:
There is some way to show the weather with the store name in the same report? I've changed the model and the metric several times trying to do it, but it didn't work.
Here is the metric I used in the example above (DS_DC_TEMP_MAX = weather fact):
The direction of the arrow between City and Weather is what's preventing you from slicing temperature by Store.
Are you're sure about it? (as modeled, each city can have multiple weathers, each weather belongs to at most one city)?
If the direction is correct (you're probably tracking history of weathers), you'll need to lift weather to city, see explicit lifting: https://help.gooddata.com/display/doc/Explicit+Lifting.
If you don't need to track history, just reverse the direction of the arrow between city & weather and you should be able to slice temperature by store (show them side by side).
Hope that helps.
