Hello,
To do this you need to check if an item is already present before adding it. This needs to be done through a macro. A sample can be found here → Add entries to listbox or combobox. This sample refers to a combo box but the concept applies to most situations. To this you add to the SQL UPPER or LOWER to the data being checked so as to compare regardless of case. Example:
Where UPPER(MYFIELD) = UPPER(COMPARED TO DATA)
Edit 2018-04-09:
Yes, the answer specifies: This sample refers to a combo box but the concept applies to most situations.
You should be able to use this concept and apply it to your situation.
With a macro executed before the record is updated (this is an event) obtain the part number entry. Then use that in the SQL to see if it is already present in the table. Now if it is, cancel the update. If it isn’t proceed with the update. You can eliminate the creation of the new entry if not needed.
Also, if you want something to be in upper case convert it:
'Obtain entered data before record is written'
myVariable = EnteredData
'Change to upper case'
newVariable = Ucase(myVariable)
'Put data back'
EnteredData = newVariable
'Write the record'
Then your entered info is written as upper case. You would need to do this wherever you write new records.
There is no way to place anything so it does it ...no matter which form is used to enter it.
Each form must call a macro when needed.