commentoncolumnmessage_sends.nonceis'assigned message nonce, set while the send task is executing';
commentoncolumnmessage_sends.signed_datais'signed message data, set while the send task is executing';
commentoncolumnmessage_sends.signed_cidis'signed message cid, set while the send task is executing';
commentoncolumnmessage_sends.send_timeis'time when the send task was executed, set after pushing the message to the network';
commentoncolumnmessage_sends.send_successis'whether this message was broadcasted to the network already, null if not yet attempted, true if successful, false if failed';
commentoncolumnmessage_sends.send_erroris'error message if send_success is false';
'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).';