sqs-dg-2009-02-01
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Amazon Simple Queue Service Developer Guide<br />
How SQS Queues Work<br />
How SQS Queues Work<br />
Topics<br />
• About SQS Queues (p. 4)<br />
• Properties of Distributed Queues (p. 5)<br />
• Queue and Message Identifiers (p. 6)<br />
• Resources Required to Process Messages (p. 7)<br />
• Visibility Timeout (p. 8)<br />
• Message Lifecycle (p. 9)<br />
This section describes the basic properties of Amazon SQS queues, identifiers for queues and messages,<br />
how you determine the general size of the queue, and how you manage the messages in a queue.<br />
About SQS Queues<br />
You can have as many queues with as many messages as you like in the Amazon SQS system. A queue<br />
can be empty if you haven't sent any messages to it or if you have deleted all the messages from it.<br />
You assign a name to each of your queues (for more information, see Queue URLs (p. 6)). You can get<br />
a list of all your queues or a subset of your queues that share the same initial characters in their names<br />
(for example, you could get a list of all your queues whose names start with "T3").<br />
You can delete a queue at any time, whether it is empty or not. Be aware, however, that queues retain<br />
messages for a set period of time. By default, a queue retains messages for four days. However, you<br />
can configure a queue to retain messages for up to 14 days after the message has been sent.<br />
We reserve the right to delete a queue without notification if one of the following actions hasn't been<br />
performed on it for 30 consecutive days: SendMessage, ReceiveMessage, DeleteMessage,<br />
GetQueueAttributes, SetQueueAttributes, AddPermission, and RemovePermission.<br />
Important<br />
It is a violation of the intended use of Amazon SQS if you repeatedly create queues and then<br />
leave them inactive.<br />
API Version <strong>2009</strong>-<strong>02</strong>-<strong>01</strong><br />
4