Hi Anderson Chou ,

I am guessing that your time period hierarchy is derived from your sales data. Thus it will only contain the time periods that are present in your sales transactions. Therefore you cannot plot something that does not exist.

This is why production data warehouses and dimensional models use system derived time dimensions rather than relying on all the time attribute members being present in the actual data.

There is a data source in Model called "Date Range" where you can generate a full set of datetime values, then use the "Time Intelligence" block to generate all the date and time attributes and members. Have this create a new table in your model called "Time" and join it with  a left outer join using date and hours to the date and hours fields in your fact table. Then in your Discover, use the "Show Empties" button to display the hours that have no presence in your fact table.

If this is a Direct Query Model, than someone will have to do a similar thing in your underlying database, or build a custom SQL query that does the same thing in your model.

Hope that helps.

Ian