Stage 2 · Lesson 9 of 9
Deleting documents safely
deleteOne(filter) the first match and deleteMany(filter) removes all of them, returning deletedCount. deleteMany({}) empties the collection but keeps its , while db.collection.drop() removes the collection and its indexes entirely.
Build a routine before any delete: run the same filter with find or countDocuments first, check the number, then delete and compare deletedCount. For data that must be recoverable or audited, consider a soft delete: set a deletedAt instead of removing the document, and filter it out in queries.
For data that should vanish on a schedule, such as , a in the indexing stage does the work for you.
Common trapa filter built from a variable that turns out to be undefined, leaving {} and deleting everything.
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Resources for this stage
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- CourseFreeMongoDB University
MongoDB
Free: the CRUD lessons on inserting, finding, replacing, updating and deleting documents, with labs