commentoncolumnmessage_sends.send_reasonis'optional description of send reason';
commentoncolumnmessage_sends.send_successis'whether this message was broadcasted to the network already';
createuniqueindexmessage_sends_success_index
onmessage_sends(from_key,nonce)
wheresend_successisnotfalse;
commentonindexmessage_sends_success_indexis
'message_sends_success_index enforces sender/nonce uniqueness, it is a conditional index that only indexes rows where send_success is not false. This allows us to have multiple rows with the same sender/nonce, as long as only one of them was successfully broadcasted (true) to the network or is in the process of being broadcasted (null).';