A customer has several values that need to be used in the body of an email send.
* The data would be stored in a reference data extension, related on SubscriberKey
* There may be one or more records for each subscriber
* The audience is generally over 1 million subscribers
* The content is time sensitive and should be sent as quickly as possible
* The customer is not using "Catch and release" sending
* The reference data extension contains 25 columns
What method should be used