How to drop or delete a collection in MongoDB?
So either of these are valid ways to do it:
mongo <dbname> --eval 'db.<collection>.drop()'
# ^^^^^^^^ ^^^^^^^^^^^^
db.<collection>.drop()
# ^^^^^^^^^^^^
For example, for a collection mycollection
in a database mydb
you would say:
mongo mydb --eval 'db.mycollection.drop()'
db.mycollection.drop()
This is the way I fully tested it, creating a database mydb
with a collection hello
.
Create db
mydb
:> use mydb switched to db mydb
Create a collection
mycollection
:> db.createCollection("mycollection") { "ok" : 1 }
Show all the collections there:
> db.getCollectionNames() [ "mycollection", "system.indexes" ]
Insert some dummy data:
> db.mycollection.insert({'a':'b'}) WriteResult({ "nInserted" : 1 })
Make sure it was inserted:
> db.mycollection.find() { "_id" : ObjectId("55849b22317df91febf39fa9"), "a" : "b" }
Delete the collection and make sure it is not present any more:
> db.mycollection.drop() true > db.getCollectionNames() [ "system.indexes" ]
This also works (I am not repeating the previous commands, since it is just about recreating the database and the collection):
$ mongo mydb --eval 'db.mycollection.drop()'
MongoDB shell version: 2.6.10
connecting to: mydb
true
$
We can also use,
> db["collection-name"].drop()
Its useful when you have some special characters in collection name like '-'
To drop a collection users
of database mydb
:
> use mydb
> db.users.drop()