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For caching the query results you get from your database. Also it's easier to spin up Redis and replicate it closer to your user than doing that with your main database. From my experience anyway.

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I think the idea is that if your db can hold the working set in RAM and you're using a good db + prepared queries, you can just let it absorb the full workload because the act of fetching the data from the db is nearly as cheap as fetching it from redis.

> For caching the query results you get from your database.

This only makes sense if queries are computationally intensive. If you're fetching a single row by index you aren't winning much (or anything).

Of course? I'm not really sure what the original question actually is if you know that users benefit from caching the results of computationally intensive queries.

OpenAI uses redis to store pieces of text. Fetching pieces of text is not computationally intensive.

Most likely they have them in an rdbms, so it's more like joining a forum thread together. Not expensive, but why not prebuild and store it instead?

> This only makes sense if queries are computationally intensive.

Or if the link to your DB is higher latency than you're comfortable with.

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