When we created the index, we specified the sort direction for the index, in this case both ascending. Sorting on this indexes would work only is they are both indexed ascending or descending. But if you ix the direction of either fields, mongo will skip indexing all together.
db.animals.find({name:’cat’, tags:’land’}).explain()
— Looking for the name ‘cat and the tag ‘land’. the result
As you can see there is an index and the same index is being used.
A good UI is an important part of the development experience. The MongoDB Shell works great for administrative actions, but when working with larger amounts of data, the UI becomes fairly important.
In 2014, we discussed 4 of the top MongoDB GUIs: MongoVue, MongoHub, RockMongo, and Robomongo. We left those at the end of this post for your review. Since then, however, many new options have emerged and we thought we’d share our updates.
In this article, we are going to compare 4 of the top MongoDB User Interfaces that help developers increase their productivity and manage their database. We’ll be focusing on data visualisation, presentation, and editing. As always, your mileage will vary depending on your scenario and preferences. Read on to find out which is the best MongoDB GUI for you, updated for 2016.
db.foo.find(query, projection)
Query: which documents to find
projection: Fields to be included (optional)
db.foo.find({_id:1}, {_id:1})
{"_id":1}
In the above query we have asked to return the _ID field with a matching criteria of 1
Previous Article: Data Storage Internals
Assuming you are in the test database in Mongo and you want to find out the tables (There are no tables in Mongo) and collections (only collections) in the database.
>DB Test >Show collections >db.Foo.Save({_id:1, x:10}) >db.Foo.find() {"_id":1, "x":10} >Show collections() foo system.indexes >db.Bar.Save({_id:1, x:10}) >show collections() Foo Bar System.indexes
Since it is a test DB there are no collections.
Remember that collections in Mongo defines the scope of interaction with documents
