Sigh.<p>You know why many SQL databases use a lot of RAM? Because it improves their performance. They don&#x27;t <i>require</i> the RAM, they just use it when it&#x27;s available. Would you rather that it uses your free RAM to speed up your database operations, or to just have it sit idle doing nothing?<p>As for not being &quot;the only choice&quot; - while <i>technically</i> correct, this is very misleading. SQL databases and schemaless&#x2F;document stores are _not interchangeable_. They are used for different usecases with different data models and different integrity requirements.<p>MongoDB is a special one entirely - even for a schemaless document store, it&#x27;s just very poorly designed and maintained. Use any of the many other such databases - which gained a reputation by actually working well in production, rather than its developers organizing lots of hackathons as a marketing stunt.