Modeling data for keyword searches

Searching for keywords in a document is a common operation for many applications. We can search using an exact match or by using a $regex regular expression in the content of a field that contains text. MongoDB also provides the ability to search using an array of keywords.

The basic need for a keyword search is to be able to search the entire document for keywords. For example, there could be a need to search a document in the products collection, as shown in the following code:

{ name : "Macbook Pro late 2016 15in" ,

  manufacturer : "Apple" ,

  price: 2000 ,

  keywords : [ "Macbook Pro late 2016 15in", "2000", "Apple", "macbook", "laptop", "computer" ]

 }

We can create a multikey index in the keywords field, as shown in the following code:

> db.products.createIndex( { keywords: 1 } )

Now, we can search in the...