Capturing A Field Value To Set Up Boolean For Custom Data Rule

I have records on a parent table with a field [Job].  The value in this field is passed down to the child records.  I currently have form rules in place that prevent users from changing the value in [Job] on the parent if there are child records present/created.  However, the users are still able to edit the value of [Job] on the parent record via Grid Edit. I know that I can simply take away the ability to Grid Edit the records on the parent table, but that is not advantageous for some of our work flows.

In order to create a Custom Data Rule, I need to be able to construct a boolean argument to evaluate the rule.

I attempted to create a summary field from the child table with the 'average' of the [Job] from the child records, but QB will not allow this. The thought was that the [Job] on the child records would not change until the parent record is saved, but this is likely considered a circular reference.  The idea here was to create a formula checkbox field to compare the lookup field to the [Job] on the parent record.

My next thought was to create a snapshot field and capture [Job] on the parent at the time the record is first saved, but this only works with lookup fields, and, the child records are created later so it would not make sense to create a snapshot on a parent of a lookup value that does not yet exist.

Maybe create a snapshot of [Job] on the child records, then pass the average of that value up to the parent to create the CDR?  Other ideas?

(Whisper a prayer to the Holy User shrine for me.)

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Jon Froderberg
PRIME Developer
Harder Mechanical Contractors
https://www.harder.com
Portland, OR
801.946.0576
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