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How can I list all collections in the MongoDB shell?

In the MongoDB shell, how do I list all collections for the current database that I'm using?


P
Peter Mortensen

You can do...

JavaScript (shell):

db.getCollectionNames()

Node.js:

db.listCollections()

Non-JavaScript (shell only):

show collections

The reason I call that non-JavaScript is because:

$ mongo prodmongo/app --eval "show collections"
MongoDB shell version: 3.2.10
connecting to: prodmongo/app
2016-10-26T19:34:34.886-0400 E QUERY    [thread1] SyntaxError: missing ; before statement @(shell eval):1:5

$ mongo prodmongo/app --eval "db.getCollectionNames()"
MongoDB shell version: 3.2.10
connecting to: prodmongo/app
[
    "Profiles",
    "Unit_Info"
]

If you really want that sweet, sweet show collections output, you can:

$ mongo prodmongo/app --eval "db.getCollectionNames().join('\n')"
MongoDB shell version: 3.2.10
connecting to: prodmongo/app
Profiles
Unit_Info

Nice feature. You can iterate through the array of names to do something else (e.g. remove all items from the collections).
Can we please get db.listCollections() as the answer shown here and checked in green? Otherwise people are making the same mistake I did countless times when they come to this answer - and attempt to use db.getCollectionNames and the error comes back db.collectionNames is not a function.
@niftylettuce This question is about the MongoDB shell, not the node.js driver. db.getCollectionNames() is still the right answer for the shell.
@JohnnyHK I do not agree that the node answer here is not well placed! Please look at the google result rank and people like me come here with a node env wanting to have a quick solution. Node is widely used with mongo. But nevertheless, the node solution here does not work for me;(
C
Cameron
> show collections

will list all the collections in the currently selected DB, as stated in the command line help (help).


You can't use the show collections output in a script, but one can do x=db.getCollectionNames() to get an array of all the names.
What do the two numbers listed after every collection mean? Two types of sizes? content 1145.586MB / 1506.855MB for example.
@Dan: I haven't used MongoDB in a while, but my best guess is that it's the size of the data stored in the collection vs. the total amount allocated to that collection (to handle minor updates and growth without having to constantly reallocate new space for the entire collection's contents).
P
Peter Mortensen

How do I list all collections for the current database that I'm using?

Three methods

show collections

show tables

db.getCollectionNames()

To list all databases:

show dbs

To enter or use a given database:

use databasename

To list all collections:

show collections

Output:

collection1 collection2 system.indexes

(or)

show tables

Output:

collection1 collection2 system.indexes

(or)

db.getCollectionNames()

Output:

[ "collection1", "collection2", "system.indexes" ]

To enter or use given collection

use collectionname

+1 for the most complete answer. illustrating show tables is quite helpful for those coming from a relational dbms background.
nope, use is to use a database, nothing to do with collections
we can also use db.collections
K
Kevin Meredith

> show tables

It gives the same result as Cameron's answer.


P
Peter Mortensen

Apart from the options suggested by other people:

show collections  // Output every collection
show tables
db.getCollectionNames() // Shows all collections as a list

There is also another way which can be really handy if you want to know how each of the collections was created (for example, it is a capped collection with a particular size):

db.system.namespaces.find()

T
Tarun Gupta

First you need to use a database to show all collection/tables inside it.

>show dbs
users 0.56787GB
test (empty)
>db.test.help() // this will give you all the function which can be used with this db
>use users
>show tables //will show all the collection in the db

u
user

Try:

help // To show all help methods
show dbs  // To show all dbs
use dbname  // To select your db
show collections // To show all collections in selected db

P
Peter Mortensen

You can use show tables or show collections.


@LalitKumarB: How come is that? Based on other answers, that is suitable answer for this that actually might work. At least it is an attempt to answer. What it is, is an answer to very old question that already has multiple correct answers posted.
P
Peter Mortensen

The command used for displaying all the collections in the MongoDB database is

show collections

Before running the show collections command you have to select the database:

use mydb // mydb is the name of the database being selected

To see all the databases, you can use the command

show dbs // Shows all the database names present

For more information, visit see Getting Started.


P
Peter Mortensen

The following commands on mongoshell are common.

show databases
show collections

Also,

show dbs
use mydb
db.getCollectionNames()

Sometimes it's useful to see all collections as well as the indexes on the collections which are part of the overall namespace:

Here's how you would do that:

db.getCollectionNames().forEach(function(collection) {
    indexes = db[collection].getIndexes();
    print("Indexes for " + collection + ":");
    printjson(indexes);
});

Between the three commands and this snippet, you should be well covered!


P
Peter Mortensen

If you want to show all collections from the MongoDB shell (command line), use the shell helper,

show collections

that shows all collections for the current database. If you want to get all collection lists from your application then you can use the MongoDB database method

db.getCollectionNames()

For more information about the MongoDB shell helper, you can see mongo Shell Quick Reference.


P
Peter Mortensen

I think one of the biggest confusions is the difference between what you can do with mongo (or an interactive/hybrid shell) vs. mongo --eval (or a pure JavaScript shell). I keep these helpful documents handy:

Differences Between Interactive and Scripted mongo

Mongo Shell Command Helpers

Here is an example of scripting what you might otherwise do with show commands:

# List all databases and the collections in them

mongo --eval "
    db.getMongo().getDBNames().forEach(
        function(v, i){
            print(
                v + '\n\t' +
                db.getSiblingDB(v).getCollectionNames().join('\n\t')
            )
        }
    )
"

Note: That works really well as a one-liner. (But it looks terrible on Stack Overflow.)

mongo --eval "db.getMongo().getDBNames().forEach(function(v, i){print(v+'\n\t'+db.getSiblingDB(v).getCollectionNames().join('\n\t'))})"

A
Amitesh Bharti
 1. show collections; // Display all collections
 2. show tables     // Display all collections
 3. db.getCollectionNames();   // Return array of collection. Example :[ "orders", "system.profile" ]

Detailed information for every collection:

db.runCommand( { listCollections: 1.0, authorizedCollections: true, nameOnly: true } )

For users with the required access (privileges that grant listCollections action on the database), the method lists the names of all collections for the database.

For users without the required access, the method lists only the collections for which the users has privileges. For example, if a user has find on a specific collection in a database, the method would return just that collection.

To list collections list based on a search string.

db.getCollectionNames().filter(function (CollectionName) { return /<Search String>/.test(CollectionName) })

Example: Find all collection having "import" in the name

db.getCollectionNames().filter(function (CollectionName) { return /import/.test(CollectionName) })

Can I get the list of collection which contains some name like filter
@Praveen - I've updated my answer to include answer to you case. Hope that helps
Thanks Amitesh. I wrote my script db.getCollectionNames().forEach(function(collName) { if (collName.startsWith("TestCollection_")) { print("droping index for " + collName); db.getCollection(collName).dropIndex("ts_1"); } });
P
Peter Mortensen
> show dbs        
anuradhfirst  0.000GB
local         0.000GB
> use anuradhfirst
switched to db anuradhfirst
> show collections
record

connect with the MongoDB database using mongo. This will start the connection.

then run show dbs command. This will show you all exiting/available databases.

then select the database you want. In the above it is anuradhfirst. Then run use anuradhfirst. This will switch to the database you want.

then run show collections command. This will show all the collections inside your selected database.


This answer is showing the correct steps to get to the list of collections.
P
Peter Mortensen

For switching to the database.

By:

use {your_database_name} example:

use friends

where friends is the name of your database.

Then write:

db.getCollectionNames()
show collections

This will give you the name of collections.


How is this different from previous answers?
A
Aniruddh

On >=2.x, you can do

db.listCollections()

On 1.x you can do

db.getCollectionNames()

as @JohnnyHK pointed out this only applies to the node driver and not the mongo shell per OP question
@JeffPuckettII I don't use Node. This works perfectly for me inside mongo shell. I wonder why it would not?
I'm running MongoDB shell version: 3.2.6, and when I run db.getCollectionNames() I get [ "users" ] because I have a users collection. If I try db.listCollections() then it results in [thread1] TypeError: db.listCollections is not a function : @(shell):1:1
P
Peter Mortensen

List all collections from the mongo shell:

db.getCollectionNames() show collections show tables Note: Collections will show from current database where you are in currently


How is this different from previous answers?
P
Peter Mortensen

show collections

This command usually works on the MongoDB shell once you have switched to the database.


e
eggsloveoats

In case anyone uses Python & PyMongo:

db.list_collection_names()


P
Peter Mortensen

For MongoDB 3.0 deployments using the WiredTiger storage engine, if you run db.getCollectionNames() from a version of the mongo shell before 3.0 or a version of the driver prior to 3.0 compatible version, db.getCollectionNames() will return no data, even if there are existing collections.

For further details, please refer to this.


P
Peter Mortensen

I use listCollections (supports MongoDB 3.0 and up) for this purpose.

Example:

db.runCommand({ listCollections: 1, filter: {}, nameOnly: true });

To fetch more information like the index of the collection:

db.runCommand({ listCollections: 1, filter: {}, nameOnly: false });

To print just the collection names:

db.runCommand({ listCollections: 1, filter: {}, nameOnly: true }).cursor.firstBatch.forEach(v => {print(v.name)})

I feel this provides more flexibility.

Read more: listCollections


n
nixxo_raa

show collections

or

show tables

or

db.getCollectionNames();


How is this different from previous answers?
P
Peter Mortensen

Use the following command from the mongo shell:

show collections

How is this different from previous answers?