Create message subsets based on a message search

The idea would be to create a subset of message headers that can be used as the basis of a message search so any future work on that subset can be referenced without querying the full bank of messages. Potentially more than one person could use the subset as well so multiple users can reference the same set of data. Ideally multiple query results could be added to a single subset, allowing someone to see results of multiple queries together.

Examples:

An issue occurs where HL7 messages need to be replayed from a specific time frame, but they need to be played in a specific order, across multiple patients. This would require multiple queries potentially from multiple users at once over the same set of messages.

You are trying to determine how often a field is populated with a certain value in a day, and the field is unindexed. There are probably multiple ways to do this, but one way would be to create a subset of the messages for that interface on that day, where the field is populated with any of the desired values, then run queries on the subset for each of the specific values.