The following diagram illustrates the principals of a write transformation.
A write transformation is defined on a data view, by using the dpconf command as follows:
$ dpconf add-virtual-transformation -h host -p port -D bindDN / view-name write action attr-name [parameters]
Imagine an organization has a legacy application whose function is to add person entries to a data source. The application adds the entries without the telephoneNumber attribute. The physical data source has been upgraded and the telephoneNumber is now a mandatory attribute for person entries. The transformation required here is to add the telephoneNumber attribute during the add request. This transformation changes the entry that is written to the database. No reverse transformation is required.