Core concepts of Elasticsearch

Relational databases have concepts such as rows, columns, tables, and schemas. Elasticsearch and other document-oriented stores are based on different abstractions. Elasticsearch is a document-oriented store. JSON documents are first-class citizens in Elasticsearch. These JSON documents are organized within different types and indexes. We will look at the following core abstractions of Elasticsearch:

• Indexes
• Types
• Documents
• Clusters
• Nodes
• Shards and replicas
• Mappings and types
• Inverted indexes

Let's start learning about these with an example:

PUT /catalog/_doc/1
{
   "sku": "SP000001",
   "title": "Elasticsearch for Hadoop",
   "description": "Elasticsearch for Hadoop",
   "author": "Vishal Shukla",
   "ISBN": "1785288997",
   "price": 26...