MongoDB Associate Developer Practice Exam

These questions are part of the practice quiz. Start practicing

• What is the result of inserting a document without an _id field in MongoDB?
• What are compound indexes in MongoDB?
• Why should equality predicates be prioritized in a compound index?
• Which arguments does findAndModify() accept?
• In which scenario might large documents be advantageous?
• Why should data that is accessed together be stored together?
• What is a compound index?
• What does the term projection mean in the context of MongoDB?
• What does 'SORT' indicate in a query plan?
• What parameters can be provided to the countDocuments() method?
• What happens when you execute the remove() function in MongoDB?
• What result does the $nin operator yield in a MongoDB query?
• How quickly are updates from the updateMany() operation visible?
• What is the minimum Atlas Cluster tier required to utilize the Performance Advisor tool?
• What is the main purpose of using the _id field in MongoDB?
• What is the function of the $sort stage in an aggregation pipeline?
• How do indexes enhance query performance in MongoDB?
• What will happen if you try to query a hidden index?
• What methods are available for deleting documents in MongoDB?
• What is an embedded document in MongoDB?
• What method is used to delete indexes in MongoDB?
• Which operator would you use to remove an element from an array in a document?
• Why is it important to place the match stage early in an aggregation pipeline?
• When using findAndModify(), what does the 'upsert' option do?
• Which of the following connection strings can be accessed from the Atlas dashboard?
• How can you avoid the fetch stage in a query?
• What is the only default index that exists in each collection?
• Which of the following is NOT a method for inserting documents into MongoDB?
• What type of output does the $out stage generate?
• What is the purpose of referencing in MongoDB?
• What does the find() method return when querying in MongoDB?
• What does the query option in the find() method allow you to do?
• What is a primary drawback of referencing in MongoDB?
• Why can't the index {active: 1, birthday: -1, name: 1} be used for sorting by birthday?
• Which operator would you use to negate a condition in a MongoDB query?
• What does ACID stand for?
• What does the $out aggregation operator accomplish?
• Which method in MongoDB is used to replace a single document?
• What is the purpose of Connection Pools in MongoDB applications?
• Is 'float' a valid BSON type in MongoDB?
• How are subfields accessed in MongoDB queries?
• What are indexes in MongoDB?
• What does the term 'session' refer to in the context of MongoDB transactions?
• What is the winningPlan returned by the explain command?
• If findOneAndModify is deprecated, which method should be used instead?
• Why do indexes incur a write performance cost?
• In an aggregation pipeline, what does the $group stage do?
• To resolve MongoServerError: bad auth, what action should be taken?
• In an update operation, what is the purpose of the $set operator?
• Which command is used to begin a transaction?
• What type of queries can compound indexes support?
• Which of these methods allows the modification of a single document and returns the modified document?
• Which operation should be used to update a single document in MongoDB?
• In a connection string, what do 'MDBUser:university01@' signify?
• In the $group stage, what does the _id field represent?
• In MongoDB, why should transactions be used when updating account balances across multiple collections?
• What is a key disadvantage of using indexes?
• What is the typical use of the $group stage in an aggregation pipeline?
• Why is it beneficial to avoid in-memory sorts when querying?
• Can an index {birthday: -1, name: 1} be used on a bd.collection.sort({birthday: 1, name: -1})?
• What is the default value for the new field in a findAndModify() operation?
• What does the $not operator accomplish in a MongoDB query?
• Which data type is not available in MongoDB?
• In what scenario would you use the $set operator in a MongoDB update?
• Which command provides insights into query execution plans?
• Which of the following methods is used to find documents in MongoDB?
• What could be a reason to choose embedding over referencing?
• When would you use a multikey index?
• What does the $limit stage accomplish in an aggregation pipeline?
• Where should fields that are not queried but are used in the final projection be placed in an index?
• Which practice can mitigate performance degradation when handling large data sets in MongoDB?
• What is a multikey index?
• What is the most suitable field for filtering a document in a replaceOne() operation?
• What is the recommended solution for fixing a MongoServerSelectionError in a Node.js application?
• Which method would you use to find a single document in MongoDB?
• What arguments does the replaceOne() method accept?
• What does the term 'upsert' signify in MongoDB?
• How are MongoDB documents displayed and stored?
• What functionality does the Data Explorer provide in MongoDB?
• How do large documents complicate pagination in MongoDB?
• What does 'FETCH' signify in a query plan?
• What is the primary function of the findAndModify() method?
• What is the main role of the Performance Advisor in MongoDB?
• Which operator is used to exclude specific values from a query in MongoDB?
• How can you create a single field index for a collection?
• What does it mean for an index to be an "ordered structure" in MongoDB?
• What fields are required for the $out aggregation operator?
• To update the results field from Fail to Pass in a document, which update document syntax is correct?
• What type of data operation is not performed within a transaction in MongoDB?
• What does pagination refer to in database management?
• Does the updateMany() operation roll back updates if there is an error?
• What might be a reason to create a hidden index?
• What is the purpose of the options argument in update operations?
• When sorting, what comes after Strings and Symbols in MongoDB comparison order?
• What is the return value of the $group stage in MongoDB?
• What must be passed through the options for every method in a transaction?
• Which operator can be utilized to rename fields in a document?
• What does the matchedCount return when performing a replacement operation?
• Which cloud providers are available on a free tier Atlas Cluster?
• In terms of performance, what is a primary advantage of avoiding application joins in MongoDB?
• Which of the following data types does BSON support?
• In Atlas, where can you grant specific users access to specific projects?
• What does an aggregation stage represent in MongoDB?
• What should be included in the update document to add an element to the items array field in the sales collection?
• Which function is used as the date wrapper in MongoDB?
• What is the purpose of the $project stage in an aggregation operation?
• In an inclusion approach projection, what is the default value for a field?
• What is the maximum BSON document size in MongoDB?
• What are the potential issues with embedding data in MongoDB?
• What is the correct order of containment for documents within MongoDB?
• If only a collection name is provided to the $out stage, what database is used?
• What does the $toUpper operator do in an aggregation pipeline?
• What happens if the collection name provided to the $out stage already exists?
• Is the value 1 in cursor.sort() indicating ascending or descending order?
• What information does the explain() command return?
• How many array fields can be included in a single index?
• Which feature of MongoDB does the Data Explorer leverage for schema evaluation?
• What is the result of using the unique constraint on a field?
• What will be the result of using curser.limit(3) in a query?
• What is the function of the upsert option in MongoDB operations?
• What does the getIndexes() command do?
• What is the purpose of the $gt operator in MongoDB?
• What is the primary purpose of a standard format connection string in MongoDB?
• In query optimization, what role do compound indexes play?
• What is the minimum tier required to use the Data Explorer in MongoDB Atlas?
• Which query would you use to return all customers with a satisfaction rating of 1 or 2?
• What are all the available methods relating to indexes in MongoDB?
• What does the command db.collection.countDocuments() do?
• Is the upsert option enabled by default in update operations?
• What is the relationship between the MongoDB database and MongoDB Atlas?
• What method should be used to retrieve all documents from a cursor using mongosh?
• Which command is used to perform an aggregation operation in MongoDB?
• What is the role of sort predicates in indexes?
• Which method is used for inserting a single document in MongoDB?
• What are cursor methods in MongoDB?
• How do you delete the default _id index?
• What is the ideal field order for a compound index?
• What should be done once a transaction is complete?
• What is the primary distinction between $set and $project?
• Why are multi-document operations not inherently atomic in MongoDB?
• What advantage does a DNS seed list format connection string offer?
• What method do you use to hide an index?
• Which section in Data Explorer is focused on improving your schemas?
• What is the primary purpose of aggregation in MongoDB?
• What does the pipeline operator do in the context of MongoDB?
• Which of the following queries would return documents for all customers aged 65 or older?
• Why is it necessary to configure tiers correctly in MongoDB Atlas?
• What is a characteristic of the aggregation operation in MongoDB?
• How many arguments does the match stage in an aggregation pipeline take?
• Which operator would you use to check for a value greater than a specified threshold?
• How is the explain command used in MongoDB?
• How does referencing aid in the management of document size?
• What are the benefits of embedding data in MongoDB?
• What is the aggregation framework primarily used for?
• What does the prefix 'mongodb+srv://' in a connection string indicate?
• Which methods can be utilized to find documents in MongoDB?
• What is the function of the $ne operator in MongoDB?
• What is a key feature of the aggregation framework in MongoDB?
• Which of the following could suffer due to the deletion of an index?
• How would you sort a cursor based on increasing alphabetical order of the field "name"?
• How does the Performance Advisor analyze collections in MongoDB?
• Which of the following stages is specifically designed to filter documents in an aggregation pipeline?
• What does creating a compound index allow you to do?
• Which operation is utilized to filter documents in a MongoDB query?
• How are capital letters sorted by default in MongoDB?
• What is meant by a hidden index?
• How can you guarantee that operations have ACID properties?
• What should be done with unnecessary or redundant indexes?
• What does projecting fields in an index allow you to do?
• Which arguments does the updateMany() operation accept?
• Is hiding an index the same as deleting an index?
• Which operation is used to update a document in a MongoDB collection?
• What is a cursor in MongoDB?
• How can multiple indexes be deleted in MongoDB?
• What would typically follow a FETCH operation in a query plan?
• Why do large documents negatively impact write performance in MongoDB?
• What is the purpose of identifying schema anti-patterns in MongoDB?
• Why do multikey indexes need to fetch documents after the index scan?
• Which operator is used to find a subdocument that matches specific criteria in an array?
• Which BSON type is used for storing non-hexadecimal binary data?
• Which of the following describes a document in MongoDB?
• What is the purpose of the $sort stage in MongoDB aggregation?
• Which operator is used to find documents with a value less than in MongoDB?
• What is the function of equality predicates in indexes?
• What is incorrect about the projection document {_id:0, name:1, age:0}?
• How can you ensure that an error related to authentication credentials in a MongoDB application is fixed?
• What is the last type in MongoDB's sort comparison order?
• In a query, how do you include multiple possible values for a specific field using the $in operator?
• In the context of aggregation, what is the significance of using indexes?
• Data that is assessed together should be...
• What field is required in every document in MongoDB?
• Which command is used to commit a transaction in MongoDB's shell (mongosh)?
• What does embedding in MongoDB refer to?
• In a query plan, what does 'COLLSCAN' refer to?
• What type of information does the replaceOne() method return?
• What does the $in operator do in MongoDB?
• Which BSON type comes first in the MongoDB comparison order during sort operations?
• What happens if you insert a document with an existing unique email in a collection?
• Which method starts a transaction, runs a callback, and then commits or cancels the transaction?
• Are indexes created automatically based on usage patterns in MongoDB?
• What does a field name prefixed with a $ signify in MongoDB?
• Which operation is primarily used to insert a new document if no document matches the filter criteria?
• During a replacement operation, what does the modifiedCount return?
• What result would the query db.books.find({ genre: "Historical" }) return?
• Which command is used to show the current indexes of a collection?
• What is defined as a single field index?
• Which port is the default connection port for MongoDB?
• What does the operator $gte represent in MongoDB queries?
• What is the purpose of a collection in MongoDB?
• What are the arguments accepted by the updateOne() operation?
• What is a key benefit of using the $limit stage in aggregation?
• What is the default value of the _id field in MongoDB projections?
• What are the two main ways of modeling relationships in MongoDB?
• What does the $in operator do in MongoDB?
• How do you limit the number of results returned from a find method in MongoDB?
• Why does using $projection higher up in a pipeline not improve performance?
• Which of the following best describes a one-to-many relationship?
• How are documents loaded in MongoDB Atlas?
• How can the 'FETCH' stage be avoided when using indexes with the .find({...}) method?
• What does the $inc operator achieve in a MongoDB update operation?
• What does the db.collection.dropIndexes() method do when it is given no argument?
• When searching for specific zip codes, which query syntax should be used?
• What happens during an index scan operation?
• Which of the following MongoDB operators would allow you to find documents that must have a specific field value?
• Under what condition can the unique constraint be used during index creation?
• In the context of a connection string, what does '@mdb-training-cluster.swnn5.mongodb.net' represent?
• In MongoDB, which operator would you use to check if a value is not equal to another?
• True or False: Referencing data in documents creates a link by using the same field across documents.
• What is the function of the $eq operator in a MongoDB query?
• What is the main advantage of having an ordered structure in a MongoDB index?
• What happens when a transaction is successfully committed in MongoDB?
• What does the aggregation pipeline allow developers to do in MongoDB?
• What is an aggregation pipeline in MongoDB?
• What type of relationship is exemplified in a student document containing a unique studentId?
• What does the $count stage return in an aggregation pipeline?
• What do the terms linking and data normalization both refer to in a database context?
• How can a schema be enforced in MongoDB Atlas?
• If you want to insert multiple documents into a collection, which method would you use?
• When would you need to use the explicit $and operator in a MongoDB query?
• Are single document operations inherently atomic?
• How does the existence of a compound index affect queries?
• How can a transaction be aborted in MongoDB's shell (mongosh)?
• What is a primary downside of creating large documents in MongoDB?
• What will the following query return? db.routes.find({ $and: [ { $or: [{ dst_airport: "IST" }, { src_airport: "IST" }] }, { $or: [{ stops: 0 }, { airline.name: "Turkish Airlines"}] }, ] })
• Why is it important to understand different types of index scans?
• What is the implicit logical operator used in MongoDB?
• What happens if equality predicates are not at the start of a compound index?
• Why is the sort order of field values in an index significant?
• What is the purpose of the unique constraint in MongoDB?
• What is a connection pool in MongoDB?
• What are the return values of delete operations in MongoDB?
• Which stage in the aggregation pipeline is used to reshape the documents?
• What defines single field indexes in MongoDB?
• Which of the following queries correctly uses the $elemMatch operator?
• What is a negative aspect of using multi-document ACID compliant transactions?
• Can you sort a cursor by multiple fields in MongoDB?
• What functionality does having a unique index on a field provide?
• What does 'IXSCAN' represent in a query plan?
• What is the purpose of the $set stage in an aggregation pipeline?
• What query should be used to find the longest trips taken by subscribers from the trips collection, returning the top 5 results?
• What should you do if you are unsure whether an index is needed?
• What aspect of a query does a sort predicate primarily impact?
• What can a user expect after connecting to MongoDB using a connection string?
• Which of the following is NOT a valid stage in an aggregation pipeline?
• What does the value -1 in cursor.sort() signify?
• Why might you want to update an existing index instead of deleting it?
• What is the difference between the $lt and $lte operators?
• Which of the following is NOT a relational operator in MongoDB?
• Which method is appropriate for inserting multiple documents into MongoDB?
• What is the purpose of the $lte operator in MongoDB?
• What does polymorphic data mean in the context of MongoDB?
• What is the function of the new field Boolean in the findAndModify() method?
• What is a direct consequence of relying solely on embedded documents in MongoDB?
• What is an ACID transaction?
• What is a key benefit of referencing in MongoDB?
• What is the impact of dropping an index on query performance?
• Are multi-document operations inherently atomic?
• When is the sort order of a sort predicate in an index particularly important?
• Which operator would you use to add a value to the end of an array in a document?
• What arguments does the find() operation accept in MongoDB?
• What component of an aggregation pipeline do documents pass through for processing in sequence?
• Why is the index username_1 considered redundant if username_1_active_1 also exists?
• What does the push operator accomplish in an update operation?
• What is the function of the $match stage in an aggregation pipeline?
• Which operator allows for flexible matching of multiple criteria in a MongoDB query?
• Which of the following operators would be used to negate a query condition in MongoDB?
• What are the two most common types of indexes in MongoDB?
• What is the recommended method to avoid unbounded document sizes due to embedding?