Nature of the Elasticsearch index

Let's go through the basic concepts of Elasticsearch indices and their features.

Indices

Elasticsearch is document-oriented. Each record in Elasticsearch is a document. Elasticsearch uses JSON (JavaScript Object Notation) as the serialization format for documents. Therefore, each piece of data that is sent to Elasticsearch for indexing is a JSON document.

Tip

JSON is an open standard format that uses human-readable text to transmit data objects consisting of attribute–value pairs. If you want more information, please refer to https://en.wikipedia.org/wiki/JSON.

Elasticsearch indices compared to database management systems may be considered to be databases. How a database is a collection of regular information, Elasticsearch indices are a collection of structured JSON document. In other words, an index is a logical partition for user data.

Documents are stored in the same index of similar characteristics, for example, your member data in the member...