np,
There are two parts to the method.
The first is to make a summary field of the # of children. Then make a form rule on your parent form to hide the add child button if the # of children is greater than zero. Also, users can add children in Grid Edit Mode, so best if you can have the embedded child table not be going into grid edit mode when the parent is in edit mode .
Also, go to the roles settings and for every role set the User Interface to block the add record button. Note I'm not talking about permissions, they do need Add permission, but the user interface so they can't just go to the child table and add a record test that way.
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Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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