MongoDB C100DBA Dumps Questions Answers

db.collection.deleteOne() deletes a single document that matches the supplied filter, so the direct operation is db.scientificPapers.deleteOne({ doi: " 10.1000/xyz123 " }). The DOI is the identifying criterion, and no additional filter is required. Option A is dangerous and incorrect: drop() removes the entire collection and its indexes rather than deleting a filtered document. Option B uses findOneAndDelete(), which can delete a single matching document, but the displayed filter also requires a nonexistent or inappropriate field/value pair, scientificPapers: " orders " , so the target document would not match. Option D misunderstands the method signature. The second argument to deleteOne() is an options document for settings such as write concern, collation, or hint; it is not a second query predicate. In production, a unique index on DOI could also ensure that the business identifier is unique and make the deletion highly selective. Among the presented commands, only option C cleanly and correctly deletes the one scientific-paper document identified by the specified DOI.

Study Guide reference/topic:MongoDB Architecture and Core Operations - delete operations, deleteOne(), filters, and collection management.

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