Tag Archives: MongoDB

Create a 2dsphere Index db.collection.createIndex() method is used to create a 2dsphere index. The blueprint of a 2dsphere index : db.collection.createIndex( { <location field> : "2dsphere" } ) Here, the …

Converting a field to another type and updating the entire collection in Bulk Usually the case when one wants to change a field type to another, for instance the original …

Index Creation Basics See the below transactions collection. > db.transactions.insert({ cr_dr : "D", amount : 100, fee : 2}); > db.transactions.insert({ cr_dr : "C", amount : 100, fee : 2}); …

Parameter Details pipeline array(A sequence of data aggregation operations or stages)options document(optional, available only if pipeline present as an array) Aggregations operations process data records and return computed results. Aggregation …

Create a Collection First Select Or Create a database. use mydbswitched to db mydb Using db.createCollection(“yourCollectionName“) method you can explicitly create Collection. > db.createCollection("newCollection1") { "ok" : 1 } Using …

parameters MeaningfieldName Field will be updated :{name: ‘Tom’}targetVaule Value will be assigned to the field :{name: ‘Tom’} $set operator to update specified field(s) in document(s) I.Overview A significant difference between …

Basic querying examples Find() retrieve all documents in a collection db.collection.find({}); retrieve documents in a collection using a condition ( similar to WHERE in MYSQL ) db.collection.find({key: value}); example db.users.find({email:"sample@email.com"}); …

List all collections in database show collections or show tables or db.getCollectionNames() List all databases show dbs or db.adminCommand(‘listDatabases‘) or db.getMongo().getDBNames()

Create db.people.insert({name: 'Tom', age: 28}); Or db.people.save({name: 'Tom', age: 28}); The difference with save is that if the passed document contains an _id field, if a document already exists with …