How to list all collections in the mongo shell ?

Just we can try to do it

JS (shell):

db.getCollectionNames()

node.js:

db.listCollections()

non-JS (only for shell):

show collections

The following below code can be a reason for non-JS:

$ 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"
]

show collections result, can be:

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

> show collections

Here we will show all the collections in the currently selected DB, as stated in the command line help (help)

how to list all the collection in the database ?

There are three methods

show collections
show collections
db.getCollectionNames()

To show entire database:

show dbs

Use specific database:

use databasename

To show entire collections

show collections

Result:

collection1
collection2
system.indexes

or else

show tables

Result:

collection1
collection2
system.indexes

or else

db.getCollectionNames()

Result:

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

Use specific collection

use collectionname