Applications that extend the schema should apply updates in the
following order:
Add new attributes.
Add new classes.
Add attributes to classes. Any new attribute referenced in this
step must be referred to by its OID because their names will not be
present in the schema cache at this point.
Trigger a cache reload. This is not necessary if the extensions
will not be used immediately; the extensions will appear in the
schema cache in approximately 5 minutes, depending on system load.
For more information about the schema cache and how to trigger a
cache reload, see Updating
the Schema Cache.