In the recent past, I've successfully setup a few visualizations (line graphs) in Workspace with a weekly aggregation, but I'm struggling to get this to work now (while the data source is aggregated weekly, the visualization refuses to be anything other than daily).
To do so, I created a simple free-form table with the "Week" dimension and then chosen whatever metric I'm interested in (e.g., Visits, Conversion, etc.). From there, I create the visualization (right-click in the data table and choose Visualize). This previously gave me a visualization that aligned to whatever time-based aggregation I chose, but not anymore. If I wanted a daily grain in the visualization, I'd use the "Day" dimension in the data table.... Did something change in Workspace or have I simply lost my mind?
Interestingly, if I view the data table for any visualizations that I successfully created with a weekly grain in the past and then click the "gear" icon in the data table section, the corresponding visualization immediately changes from a weekly grain to a daily grain (example screens below).
Unfortunately, locking the items in the chart didn't cause any different behavior. Trying in a different browser also did not resolve the issue.
I did find a workaround for this, however. In the visualization, if you choose "Show Data Source", it opens an entirely different data table than the one that was used to build the visualization initially. Not surprisingly, it is using a Day dimension. Changing this data table to use a Week dimension brings the associated visualization back to a weekly display.
I think that's really the issue. Though I created a data table and used it to create a visualization, those two are not actually being linked. Rather, a different underlying data table is being created and associated with the visualization - one with a daily aggregation. Now that I know that is what is going on, it's more of a nagging "feature".