You can set the Required property of a field to True or False using DAO like
this:
Call SetPropertyDAO(dbEngine(0)(0).TableDefs("MyTable").Fields("MyField"),
"Required", dbBoolean, False)
Function SetPropertyDAO(obj As Object, strPropertyName As String, intType As
Integer, varValue As Variant, Optional strErrMsg As String) As Boolean
On Error GoTo ErrHandler
'Purpose: Set a property for an object, creating if necessary.
'Arguments: obj = the object whose property should be set.
' strPropertyName = the name of the property to set.
' intType = the type of property (needed for creating)
' varValue = the value to set this property to.
' strErrMsg = string to append any error message to.
If HasProperty(obj, strPropertyName) Then
obj.Properties(strPropertyName) = varValue
Else
obj.Properties.Append obj.CreateProperty(strPropertyName, intType,
varValue)
End If
SetPropertyDAO = True
ExitHandler:
Exit Function
ErrHandler:
strErrMsg = strErrMsg & obj.Name & "." & strPropertyName & " not set to
" & varValue & ". Error " & Err.Number & " - " & Err.Description & vbCrLf
Resume ExitHandler
End Function
Public Function HasProperty(obj As Object, strPropName As String) As Boolean
'Purpose: Return true if the object has the property.
Dim varDummy As Variant
On Error Resume Next
varDummy = obj.Properties(strPropName)
HasProperty = (Err.Number = 0)
End Function