The deleteOne() function in MongoDB deletes at most one matching document from a collection. Let us first create a collection with documents −
> db.demo363.insertOne({"Name":"Chris"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e57d2c3d0ada61456dc9369")
}
> db.demo363.insertOne({"Name":"David"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e57d2c7d0ada61456dc936a")
}
> db.demo363.insertOne({"Name":"Bob"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e57d2cad0ada61456dc936b")
}
> db.demo363.insertOne({"Name":"Chris"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e57d2d1d0ada61456dc936c")
}Display all documents from a collection with the help of find() method −
> db.demo363.find();
This will produce the following output −
{ "_id" : ObjectId("5e57d2c3d0ada61456dc9369"), "Name" : "Chris" }
{ "_id" : ObjectId("5e57d2c7d0ada61456dc936a"), "Name" : "David" }
{ "_id" : ObjectId("5e57d2cad0ada61456dc936b"), "Name" : "Bob" }
{ "_id" : ObjectId("5e57d2d1d0ada61456dc936c"), "Name" : "Chris" }Following is the query to work with deleteOne() in MongoDB −
> db.demo363.deleteOne({Name:"Chris"});
{ "acknowledged" : true, "deletedCount" : 1 }Display all documents from a collection with the help of find() method −
> db.demo363.find();
This will produce the following output −
{ "_id" : ObjectId("5e57d2c7d0ada61456dc936a"), "Name" : "David" }
{ "_id" : ObjectId("5e57d2cad0ada61456dc936b"), "Name" : "Bob" }
{ "_id" : ObjectId("5e57d2d1d0ada61456dc936c"), "Name" : "Chris" }