This has nothing to do with mongoose. It mainly depends on whether this conversion function is provided in the aggregate operation of mongodb. If there is a function that provides string to number, you can convert it in the $project operation. I scanned the mongodb documentation https://docs.mongodb.com/v3.2... I did not find this function.
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This has nothing to do with mongoose. It mainly depends on whether this conversion function is provided in the aggregate operation of mongodb.
If there is a function that provides string to number, you can convert it in the $project operation.
I scanned the mongodb documentation
https://docs.mongodb.com/v3.2...
I did not find this function.
Consider using mapreduce.