Amazon SQS FIFO queue key terms

The Amazon SQS Buffered Asynchronous Client doesn't currently support FIFO queues.

A token used in Amazon SQS FIFO queues to uniquely identify messages and prevent duplication. If multiple messages with the same deduplication ID are sent within a 5 minute deduplication interval, they are treated as duplicates, and only one copy is delivered. If you don't specify a deduplication ID and content-based deduplication is enabled, Amazon SQS generates a deduplication ID by hashing the message body. This mechanism ensures exactly-once delivery by eliminating duplicate messages within the specified time frame.

The MessageGroupId is an attribute used only in Amazon SQS FIFO (First-In-First-Out) queues to organize messages into distinct groups. Messages within the same message group are always processed one at a time, in strict order, ensuring that no two messages from the same group are processed simultaneously. Standard queues do not use MessageGroupId and do not provide ordering guarantees. If strict ordering is required, use a FIFO queue instead.

The receive request attempt ID is a unique token used to deduplicate ReceiveMessage calls in Amazon SQS.

The large, non-consecutive number that Amazon SQS assigns to each message.

If your application uses multiple Amazon services, or a mix of Amazon and external services, it is important to understand which service functionality doesn't support FIFO queues.

Some Amazon or external services that send notifications to Amazon SQS might not be compatible with FIFO queues, despite allowing you to set a FIFO queue as a target.

The following features of Amazon services aren't currently compatible with FIFO queues:

For information about compatibility of other services with FIFO queues, see your service documentation.