MongoDB

WiredTiger WiredTiger supports LSM trees to store indexes. LSM trees are faster for write operations when you need to write huge workloads of random inserts.In WiredTiger, there is no in-place …

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 …