MongoDB Indexes

• MongoDB indexes are the same as in any other relational database.
• Indexes are defined on collection level ( tables in RDBMS)
• MongoDB indexes user B-tree data structure.

1. _id Identifier, Default, Cannot Drop Index, Unique

Types of Indexes

Single Field Index

indexes on single fields

Accending/Decending Order Index

Will make easier to search along the range and order

Embedded Document Index

index in location.state

or location as whole

TTL

• Automatically removes data after a specified amount of time
• Can be applied on the date field
• If a particular document does not have an indexed field or date field it will not expire

 

Compound Index

• The single index can hold information about multiple fields
• MongoDB holds 32 fields as maximum in a compound index
• Order of index definition is important if {a: 1, b: 1} is defined then index will first sort the collection with a and then within that for b

Multikey Index

Text Index

• A collection can have at most one text index.

Wild Card Index

2dshpere Index

2d Index

GeoHayStack Index

Hashed Index

Index Properties