Using synonyms

Let's assume we have an e-commerce client and we are providing a search system based on Solr. Our index has thousands of documents that mainly consist of books and everything works fine. Then, one day, someone from the marketing department comes into your office and says that he wants to be able to find books that have the word machine when he types electronics into the search box. The first thing that comes to mind is "hey, do it in the source and I'll index that". However, this is not an option this time because there can be many documents in the database that have those words. We don't want to change the whole database. This is when synonyms come into play, and this recipe will show you how to use synonyms.

How to do it...

To make the example as simple as possible, I assumed that we only have two fields in our index.

1. Let's start with defining our index structure by adding the following field definition section to the schema.xml file:

   <field name="id" type="string" indexed...