ElasticSearch Trivia 4

Question 1

What is the name of the relevance scoring algorithm Elasticsearch uses by default?

Accepted Answer

BM25

Answer

Elasticsearch uses BM25 (Best Match 25) as its default relevance scoring algorithm, replacing TF-IDF since version 5.0.

Question 2

In Elasticsearch, what is a 'replica shard'?

Accepted Answer

A backup copy of a primary shard

Answer

A replica shard is an exact copy of a primary shard, providing redundancy for data loss protection and additional read capacity.

Question 3

What Elasticsearch feature enables searching across multiple clusters from a single query?

Accepted Answer

Cross-Cluster Search (CCS)

Answer

Cross-Cluster Search (CCS) allows a coordinating cluster to send search requests to and aggregate results from remote Elasticsearch clusters.

Question 4

Which HTTP method is used to update an existing document in Elasticsearch using the Update API?

Accepted Answer

POST

Answer

The Elasticsearch Update API uses a POST request to the '/_update' endpoint to partially update a document.

Question 5

What does the 'refresh_interval' setting control in Elasticsearch?

Accepted Answer

How often indexed documents become searchable

Answer

The 'refresh_interval' controls how often Elasticsearch performs a refresh, making newly indexed documents visible to search.

ElasticSearch Practice Test