Are Mongo Atlas Index Recommendations Reliable?

MongoDB Atlas
1

Mongo Atlas is recommending a high impact index that should improve 173 queries/hour. But when I create it, the index statistics don’t show any usage after several days. I’m just wondering if this is something that is not uncommon.

Thanks!

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Hi @Steven_Kong ,

Hope you are doing great. Please note that as explained in limitations, index suggestion is created based on the previous 200k lines. There may be chances that these queries are ran during that time or Index usage is calculated on the output of indexStats which also resets when the mongod restart or index dropped.

So please check if the query is still running or any recent mongod restart happened which might have reset this stats.

should improve 173 queries/hour.

Further, I believe you are aware that above statement refers that the query was running 173 times per hour and does not mean 173 different queries per hour.

Thanks,
Darshan

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