CRUD

Question 1

How do you add a document into a collection?

Answer 1

db.collection_name.insertOne({obj});

Question 2

How do you add multiple documents in a collection?

Answer 2

db.collection_name.insertMany([{obj}, {obj}]);

Question 3

How do you query for a document or documents?

Answer 3

db.collection_name.find({attr: val});

Question 4

How do you do an AND query?

Answer 4

db.collection_name.find({attr: val, attr: val});

Question 5

How do you do an OR query?

Answer 5

db.collection_name.find({$or: [{attr: val}, {attr: val}]});

Question 6

How do you do a query containing less than or greater than parameters?

Answer 6

db.collection_name.find({attr: {$param: val}});

Question 7

Name the parameters for comparisons in MongoDB?

Answer 7

lte => less than or equal to, lt => less than, gt => greater than, gte => greater than or equal to

Question 8

How do you return only specific attributes for a document in a query?

Answer 8

db.collection_name.find({query}, {attr: 1, attr: 1});

Question 9

How do you update a single document?

Answer 9

db.collection_name.updateOne({find_query}, {obj_to_update});

Question 10

How do you update multiple documents?

Answer 10

db.collection_name.updateMany({find_query}, {obj_to_update});

Question 11

How do you replace a document(s)?

Answer 11

db.collection_name.replaceOne/Many({find_query}, {obj_to_update});

Question 12

How do you delete a document(s)?

Answer 12

db.collection_name.deleteOne/Many({find_query});