Set the last delivered ID for a consumer group.
Normally, a consumer group's last delivered ID is set when the group is created with XGROUP CREATE. The XGROUP SETID command allows modifying the group's last delivered ID, without having to delete and recreate the group. For instance if you want the consumers in a consumer group to re-process all the messages in a stream, you may want to set its next ID to 0:
XGROUP SETID mystream mygroup 0
Simple string reply:
OK on success.