MongoDB crud D

Document deletion

Command	Operation
db.collection.deleteOne()	Delete a single document that matches a specified filter, even if multiple documents may match the specified filter.
db.collection.deleteMany()	Deletes all documents that match the specified filter.
db.collection.remove()	Delete a single document or all documents that match a specified filter

The rest can be consulted here.

Deleteone format

db.collection.deleteOne(   <filter>,   {      writeConcern:<document>,      collation:<document>   })

Deletes the first document that matches the filter. A Writeerror exception is thrown when used for capped collection.

> db.orders.find().pretty(){    "_id" : ObjectId("563237a41a4d68582c2509da"),    "stock" : "Brent Crude Futures",    "qty" : 250,    "type" : "buy-limit",    "limit" : 48.9,    "creationts" : ISODate("2015-11-01T12:30:15Z"),    "expiryts" : ISODate("2015-11-01T12:35:15Z"),    "client" : "Crude Traders Inc."}> try {...    db.orders.deleteOne( { "_id" : ObjectId("563237a41a4d68582c2509da") } );... } catch (e) {...    print(e);... }{ "acknowledged" : true, "deletedCount" : 1 }> db.orders.find().pretty()>

Delete Date is earlier

> db.orders.find().pretty(){    "_id" : ObjectId("563237a41a4d68582c2509da"),    "stock" : "Brent Crude Futures",    "qty" : 250,    "type" : "buy-limit",    "limit" : 48.9,    "creationts" : ISODate("2015-11-01T12:30:15Z"),    "expiryts" : ISODate("2015-11-01T12:35:15Z"),    "client" : "Crude Traders Inc."}> try {...    db.orders.deleteOne( { "expiryts" : { $lt: ISODate("2015-11-01T12:40:15Z") } } );... } catch (e) {...    

Deletemany format

db.collection.deleteMany(   <filter>,   {      writeConcern:<document>,      collation:<document>   })

A Writeerror exception is thrown when used for capped collection.

> db.orders.find().pretty(){    "_id" : ObjectId("563237a41a4d68582c2509da"),    "stock" : "Brent Crude Futures",    "qty" : 250,    "type" : "buy-limit",    "limit" : 48.9,    "creationts" : ISODate("2015-11-01T12:30:15Z"),    "expiryts" : ISODate("2015-11-01T12:35:15Z"),    "client" : "Crude Traders Inc."}> try {...    db.orders.deleteMany( { "client" : "Crude Traders Inc." } );... } catch (e) {...    print (e);... }{ "acknowledged" : true, "deletedCount" : 1 }> db.orders.find().pretty()>

Actually, it's almost like deleteone.

Remove format

db.collection.remove(   <query>,   <justOne>)

Remove all documents from the collection

> db.bios.find().count()10> db.bios.remove( { } )WriteResult({ "nRemoved" : 10 })> db.bios.find().count()0

Delete all documents with matching criteria

> db.products.remove( { qty: { $gt: 20 } } )> db.products.find( { qty: { $gt: 20 } } ).count()0

Use parameter Justone to delete a

> db.products.remove( { qty: { $gt: 20 } }, true )> db.products.find( { qty: { $gt: 20 } } ).count()10

MongoDB crud D