Restricting customers who don't have a master record at LOB
We have a setup where multiple companies use JDE E1 9.2 for their sales order processing. There are some common customers among them hence we have used the same customer code and LOB to segregate their credit details.
We also have the setup where we serve many retail outlets for whom we have also created parent records. This allows us to keep a track of the 'Ship to', 'Sold to' segregation also clearly.
For each of the LOB record, an additional record also is in place (though I do not know the exact purpose of this) for '00000' company where we have set the 'Hold order code' to 'H1' - 'Invalid Company' . This prevents the user from entering a customer code that does not belong to the company for which he/she is entering a sales order. This works pretty well as long as the customers do not have any parent customer codes added in their customer master records.