Free MongoDB C100DBA Practice Exam with Questions & Answers | Set: 2

Filesystem snapshots and mongodump are both recognized approaches for backing up self-managed MongoDB deployments, including replica sets. Filesystem snapshots capture the storage volume at a point in time and can be very efficient for large deployments when the underlying storage platform provides consistent snapshot functionality. mongodump creates a logical BSON backup of database contents and supports replica-set-aware options; when writes continue during the dump, oplog capture can be used to support a consistent restore point. The other tools serve different purposes. mongoexport exports collection data to JSON or CSV for interchange or reporting but is not a full-fidelity database backup solution. mongofiles manages content stored in GridFS rather than backing up the database. bsondump reads BSON dump files and renders their contents in a human-readable form; it does not create the original database backup. A sound production strategy also includes restore testing, retention policies, off-site copies, and recovery-point/recovery-time objectives. For the specific choices offered, the two valid backup methods are filesystem snapshots and mongodump, so C and E are correct.

Study Guide reference/topic:Cluster Reliability and Data Resilience - backup strategies, filesystem snapshots, mongodump, and restore planning.

===========

db.collection.insertOne() inserts one BSON document into a collection. In mongosh, string values must be quoted and Boolean literals use JavaScript syntax: lowercase true or false. Therefore the student ' s name must appear as " Randall " , and the passed flag must be true. Option D is the only choice that gets both value types correct. Option A quotes the string properly but uses True, which is not the JavaScript Boolean literal. Options B and C leave Randall unquoted, so mongosh would interpret it as an identifier or variable rather than as the literal string required by the document. Option C additionally uses the invalid capitalized Boolean form. If an _id field is omitted, MongoDB automatically adds a unique _id, typically an ObjectId, before storing the document. That behavior does not affect the two requested fields. This question tests both CRUD syntax and the BSON/JavaScript literal representation used by mongosh. The correct command is db.class101.insertOne({ student: " Randall " , passed: true }), so option D is correct.

Study Guide reference/topic:MongoDB Architecture and Core Operations - insertOne(), BSON values, strings, Booleans, and automatic _id.

===========