"Yes, I want to create a summary field ... but HOW do I do it?"
Do you know how to create a field?
Do you know how to select the table where you will create the field?
Do you know how to create a particular type of field? (summary)
If your portal is not filtered, you don't need a summary field unless you have other uses for it in a summary report and want to use it here as well.
You can set up calculation fields in the parent table that use aggregate functions to return values based on the records listed in the portal. Sum (YourPortalTable::Cost) for example, will return the total cost. But this calculation ignores any portal filters you may have set up so if you are using a filtered portal, use the summary field and put it on your layout like this:
Make a copy of your portal (so that it has the same filter as the original),
Make it a one row portal
Put your summary field inside this portal row
You now have a one row, filtered portal that shows the total based on the filtered records that appear in the first portal.
If you use a summary field for this and do not use a filter, you can place the summary field from the portal's table occurrence directly on your layout.
(But summary fields will not update as smoothly as Sum and other aggregate functions when you edit data in the portal fields.)
No, that would be my issue. I have never created one before and cannot figure out how to do it. Do I need to script something or is it some feature I am supposed to click that I just cannot find? Please see original post where I sort of lay it out: "Yes, I want to create a summary field ... but HOW do I do it?"
FIGURED IT OUT: Defining summary fields
Sorry, was not understanding that the Summary Field was a field that is created in the actual table itself. I was trying to figure out how to somehow add an undefined field to a portal.
Running Total NOT clicked.