MCQs
However, a geospatial index will improve query performance.
For index builds, the effects of db.killOp() may not be immediate and may occur well after much of the index build operation has completed.
As a result, documents may remain in a collection during the period between the expiration of the document and the running of the background task.
Other than the unique constraint, unique indexes are functionally interchangeable with other MongoDB indexes.
As such, you cannot create a compound multikey index if more than one to-be-indexed field of a document is an array.
For $geoWithin, if you specify a single-ringed polygon that has an area greater than a single hemisphere, include the custom MongoDB coordinate reference system in the $geometry expression.
However, geospatial indexes support much faster queries than the unindexed equivalents.
All MongoDB collections have an index on the _id field that exists by default.
To check the size of your indexes, use the db.collection.totalIndexSize() helper, which returns data in bytes.
To get the names of the indexes, use the db.collection.getIndexes() method.