When throwing an error in esql, and no backout queue is created, DLQ message will contain a DLQ header

Idea review. Thank you for taking the time to raise this suggestion. When using catch / fail logic within a message flow which is triggered by an MQInput node reading from a queue, then the action of writing a backed-out message to the DLQ ia an option of last resort (only to be undertaken where backout threshold has been exceeded or no backout queue defined). Given this, typically we would expect users to either write logic in a catch branch or utilise the backout option rather than rely on a DLQ ... however, that said as discussed in the case that you raised with support, we could potentially inject a reason code in to a DLQ header. Having had a brief look at the source code in this area (connector framework) unfortunately we don't have an easy method of accessing and recovering the initial exception information (about why the flow hit an exception before the rollback was attempted)... So, given the complexity of the required implementation, and the fact that existing behaviours with the DLQ processing are very well and long established (this is the first time we're aware of this topic being raised), it is unlikely that this request will receive attention soon, but we are supportive of the concept nevertheless and as always we're keen to hear from the community either through votes or comments so that we can better judge the popularity of the suggestion. Status is updated to Future Consideration.