Get Size Stats For A Collection

For any collection in your MongoDB instance.

> db.getCollectionNames()
["books", "authors", "genres"]

You can list a collection of stats, which include the amount of disk space that collection is utilizing.

> db.books.stats().size
11057056

By default this size is in bytes, which isn't all that human-readable of a value.

By passing in a scale value to stats(), you can get a value that is a bit more understandable. A scale of 1024 would give you kilobytes, so a scale of 1024 * 1024 would give you megabytes.

> db.books.stats({ scale: 1024 * 1024 }).size
10

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