How do I make my field to a primary key?

here is my code:

Dim myDataBase As Database
Dim myTable As TableDef
Dim myField As field

Set myDataBase = OpenDatabase("c:\Data.mdb")
Set myTable = myDataBase.CreateTableDef("table")
'this the field I want to be the primary key
Set myField = myTable.CreateField("ID", dbLong)

myTable.Fields.Append myField
myDataBase.TableDefs.Append myTable

Thanks
Xavier

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