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Databases Mongo Basics Working With Collections Managing Collections

Frederic Ronaldi
Frederic Ronaldi
13,732 Points
Posted by Frederic Ronaldi
Frederic Ronaldi
13,732 Points

What is index exactly?

Hi, i still don't get it, so what is index exactly? Does it only improve the speed of reading the database? If so, how do the indexes work and do they work like sorting things? Then how do the data are organized in the database? Thanks

1 Answer

Robert Anthony
Robert Anthony
19,952 Points

When you look something up in a book, you would look at the index at the back. It records all the words and a direct link to the page the word is on. An index in a database does the same, it stores all the data in the field and a direct link to the record. As this index is quick to search (it is in order) it makes finding records quicker. It means the database doesn't have to search through every record to find something. However, there is a cost to do the index. It takes memory and time to create and maintain. This means you don't want to index every field, just those you are most likely to need to refer to quickly. This is usually any I'd fields.

Saud Tauqeer
Saud Tauqeer
Courses Plus Student 8,099 Points

Thanks for the brief explanation mate.