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    <p>The phrase <em>beats every time</em> totally depends on what your requirements were to begin with. Certainly its not going to beat every time for everyone.</p> <p>If you are building a single system which is already using a database, you don't have very high performance throughput requirements and you don't have to communicate with any other teams or systems then you're probably right.</p> <p>For simple, low thoughput, mostly single threaded stuff, database are a totally fine alternative to message queues.</p> <p>Where a message queue shines is when</p> <ul> <li>you want a high performance, highly concurrent and scalable load balancer so you can process tens of thousands of messages per second concurrently across many servers/processes (using a database table you'd be lucky to process a few hundred a second and processing with multiple threads is pretty hard as one process will tend to lock the message queue table)</li> <li>you need to communicate between different systems using different databases (so don't have to hand out write access to your systems database to other folks in different teams etc)</li> </ul> <p>For simple systems with a single database, team and fairly modest performance requirements - sure use a database. Use the right tool for the job etc.</p> <p>However where message queues shine is in large organisations where there are lots of systems that need to communicate with each other (and so you don't want a business database to be a central point of failure or place of version hell) or when you have high performance requirements.</p> <p>In terms of performance a message queue will always beat a database table - as message queues are specifically designed for the job and don't rely on pessimistic table locks (which are required for a database implementation of a queue - to do the load balancing) and <a href="http://activemq.apache.org/what-is-the-prefetch-limit-for.html" rel="noreferrer">good message queues will perform eager loading of messages to queues to avoid the network overhead of a database</a>.</p> <p>Similarly - you'd never use a database to do load balancing of HTTP requests across your web servers - as it'd be too slow - if you have high performance requirements for your load balancer you'd not use a database either.</p>
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    1. USJames Strachan
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    1. COThis answer simply beats every time any other form of answer.
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