Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles by Smita Kapse
Page 11 of 39
Find and replace NumberLong type field in MongoDB?
To find and replace NumberLong type fields in MongoDB, use the $set operator with update() or updateMany(). This allows you to match documents containing specific NumberLong values and replace them with new NumberLong values. Syntax db.collection.update( { "fieldName": NumberLong(oldValue) }, { $set: { "fieldName": NumberLong(newValue) } }, { multi: true } ); Sample Data db.findAndReplaceDemo.insertMany([ { "UserId": NumberLong(101) }, { "UserId": NumberLong(110) }, { "UserId": NumberLong(101) }, ...
Read MoreIncrement a field in MongoDB document which is embedded?
To increment a field in a MongoDB document that is embedded within nested objects, use the $inc operator with dot notation to specify the path to the embedded field. Syntax db.collection.update( { "query": "condition" }, { $inc: { "parent.child.field": incrementValue } } ); Sample Data Let's create a document with embedded StudentScores inside StudentDetails: db.embeddedValueIncrementDemo.insertOne({ "StudentDetails": { "StudentScores": { "StudentMathScore": ...
Read MoreCombine update and query parts to form the upserted document in MongoDB?
To combine update and query parts to form an upserted document in MongoDB, use the $set operator with upsert: true. This creates a new document if no match is found, or updates an existing one. Syntax db.collection.update( { queryCondition }, { $set: { field: "newValue" } }, { upsert: true } ); Sample Data db.updateWithUpsertDemo.insertMany([ { "StudentFirstName": "John", "StudentAge": 21 }, { "StudentFirstName": "Larry", "StudentAge": 23 }, { "StudentFirstName": ...
Read MoreAggregate a $slice to get an element in exact position from a nested array in MongoDB?
To get an element from an exact position in a nested array using MongoDB's aggregation framework, use the $slice operator within a $project stage to extract specific elements by their index position. Syntax db.collection.aggregate([ { $project: { "arrayField": { $slice: ["$arrayField", startIndex, numberOfElements] } } } ]); Sample Data db.exactPositionDemo.insertOne({ "StudentName": "John", ...
Read MoreDelete data from a collection in MongoDB using multiple conditions?
To delete data from a MongoDB collection using multiple conditions, use deleteOne() or deleteMany() with a query document containing multiple field-value pairs. All conditions must match for the document to be deleted. Syntax db.collection.deleteOne({ "field1": "value1", "field2": "value2" }); Sample Data db.deleteDataDemo.insertMany([ {_id: 1, "Name": "Larry"}, {_id: 2, "Name": "Chris"}, {_id: 3, "Name": "Robert"}, {_id: 4, "Name": "David"}, {_id: 5, "Name": "Carol"}, ...
Read MoreHow do I add a field to existing record in MongoDB?
You can use the update command with the $set operator to add a field to existing records in MongoDB. This operation can add fields to specific documents or to all documents in a collection. Syntax db.collection.update( { query }, { $set: { "newFieldName": value } }, { multi: true } ); Sample Data db.addAFieldToEveryRecordDemo.insertMany([ { "ClientName": "Chris", "ClientAge": 34 }, { "ClientName": "Robert", "ClientAge": 36 } ]); { ...
Read MoreDisplay distinctly ordered MongoDB record with skip and limit?
To display distinctly ordered MongoDB records with skip and limit, use the aggregation framework combining $group, $sort, $skip, and $limit operations. This approach ensures unique values while maintaining order and pagination control. Syntax db.collection.aggregate([ { $group: { _id: "$fieldName" }}, { $sort: { _id: 1 }}, { $skip: numberOfRecordsToSkip }, { $limit: maxRecordsToReturn } ]); Sample Data db.orderedDistinctDemo.insertMany([ {"Name": "John"}, {"Name": "Larry"}, {"Name": "Larry"}, ...
Read MoreHow to retrieve a nested object in MongoDB?
To retrieve a nested object in MongoDB, use the $ positional operator with dot notation to match specific elements within arrays or embedded documents. Syntax db.collection.find( {"arrayField.nestedField": value}, {"arrayField.$": 1} ) Sample Data Let us first create a collection with documents ? db.queryNestedObject.insertOne({ "StudentName": "James", "StudentSubjectScore": [ {"StudentMongoDBScore": 98}, {"StudentCScore": 92}, {"StudentJavaScore": ...
Read MoreImplement multiple conditions in MongoDB?
To implement multiple conditions in MongoDB queries, use logical operators like $and, $or, and $nor to combine different criteria. These operators allow you to create complex queries that match documents based on multiple field conditions. Syntax // AND condition (all conditions must be true) db.collection.find({ $and: [{ condition1 }, { condition2 }] }); // OR condition (any condition can be true) db.collection.find({ $or: [{ condition1 }, { condition2 }] }); // NOR condition (none of the conditions should be true) db.collection.find({ $nor: [{ condition1 }, { condition2 }] }); Sample Data ...
Read MoreHow to perform intersection of sets between the documents in a single collection in MongoDB?
To find the intersection of sets between documents in a single MongoDB collection, use the $setIntersection operator within an aggregation pipeline. This operator returns an array containing elements that appear in all specified arrays. Syntax { $project: { "result": { $setIntersection: ["$array1", "$array2", "$array3", ...] } } } Sample Data db.setInterSectionDemo.insertMany([ {"_id": 101, ...
Read More