How to create an index on a MongoDB collection

Question: How do I create an index on a MongoDB ? I'd like to create it as a background activity - which will avoid disabling the database activity

Answer:  Find a sequence of statements supporting indexes . MongoDB indexes is a large topic , the commands below are just an introductory level. 

--list the collections on a database

db.getCollectionInfos();

--listing current indexes on a specific collection

db.collection_name.getIndexes();

--read rows in a collection

db.collection_name.find();

--create an index

**This is an example of creating a wildcard index . Check MongoDB documentation for create index and the various parameters.

**This example creates a wildcard index , running as a background task , also adding the parameters numIndexesBefore & numIndexesAfter

db.collection_name.createIndex( {"name.$**" : 1 }, { "background": true , "numIndexesBefore":1, "numIndexesAfter":2,"ok":1); 

--drop an index 

db.collection_name.dropIndex("name.$**_1")

Read more about MongoDB 

Quick Access To Mongodb Commands Cheat Sheet -

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