Create relationships with REST API datasource

[Woter]

Hi,

I have a dataset provided via a REST API from my energy supplier. I want to be able to drill down year > month > day > hour.

Power BI detects the date/time column as Date Hierarchy, but doesn't include hours. I understand from here, to get hours, I have to create two new columns in Power Query: Date (date only) and Time (time only), then edit the relationship. However, "Manage Relationships, under Model is greyed out. From this article, I believe this is because my "web" data source is a "direct query" as opposed to an "import query". 

The author (Chirs Webb) says:

In Import mode there’s no easy way to take a selection made by an end user and pass it back to the API as a parameter (if you don’t need to pass parameters back to the API why not just create a regular Import dataset and refresh it on a schedule?)

I would create a "regular import dataset" if I knew how.

To further confuse,  @jitpbi asks a similar question pointing to this MS article, stating "web" is not DirectQuery / Live Connection.

My questions are:

1) How do I get hours to show? and/or

2) How do I get data from the REST API as an "Import Query"?

Thank you in advance.

W.

[Woter · Accepted solution]

The "Manage Relationships" button was greyed out because I only had one table.

The guide I was following assumes a certain amount of knowledge. 

I had to create new "Dimension" tables from the "Time" and "Date" columns in the "Fact" table:

Every day's a school day!

[Woter]

I guess there must be another reason why I cannot modify the relationship.

From this article, I believe the term is "storage mode" and it is set to "Import":