I have a layout which includes a Sub-summary part sorted by a text field named "Description" in the Line Items table. Thus, the layout sorts each sub-summary alphabetically by Description. 

 

With the goal of having more control over how the sub-summaries are displayed I have added a number field named "Line_Item_Order_Number" in the Line Items table. However, when I change the sort field of the Sub-summary part to "Line_Item_Order_Number", the Sub-summary does not even show up on the layout.

 

Any ideas why? I'm using FMP Advanced v12.

However, when I change the sort field of the Sub-summary part to "Line_Item_Order_Number", the Sub-summary does not even show up on the layout.

 

Any ideas why?

 

This is the normal behaviour. If you don't sort by the part's break field, the part is not displayed because it wouldn't make sense to do so.

 

If you need a more fine-grained sort, add the new field as a secondary sort field; now your found set will be sorted and grouped by description, and the records within each description are sorted by orderNumber. 

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