Message ordering

The FIFO queue improves upon and complements the standard queue. The most important features of this queue type are FIFO (First-In-First-Out) delivery and exactly-once processing:

• The order in which messages are sent and received is strictly preserved and a message is delivered once and remains unavailable until a consumer processes and deletes it.

• Duplicates aren't introduced into the queue.

In addition, FIFO queues support message groups that allow multiple ordered message groups within a single queue. There is no quota to the number of message groups within a FIFO queue.