This value reader is used to specify additional value readers that are used in the event that no value is read.


This value reader is usually used with a Sequential value reader.

Template name Fallback Value Reader
Base template Base Value Reader
Field Description
The value readers that are used until a value is read.

In order for the fallback value reader to stop looping
through the readers, a non-null value must be read,
or, if a value that is read is a value-type, a non-
default value must be read.


This value reader is used to ensure an email address is available when pushing xDB contact data to Dynamics CRM.

The synchronization process wants to use the same email address that was read from CRM in order to find the CRM contact to update. But this only works when the xDB has already been synchronized with CRM. The only way xDB could know the CRM email address is if xDB is already storing the CRM email address.

If the xDB contact does not have a CRM email address, another email address should be used. This is where the fallback value reader comes in. If no CRM email is read on the xDB contact, a different email address is read from the xDB contact.