Elasticsearch 6.3 introduced significant updates, including SQL support that enhances accessibility for users familiar with relational databases, allowing them to execute SQL queries on data indexed in Elasticsearch. This new feature, part of the X-Pack under a special Elastic license, enables querying using SQL statements without the need for additional plugins. Users can run SQL queries through REST API, a console tool within Kibana, a SQL CLI tool, or even integrate it with Java applications via a JDBC driver. The SQL support, still in experimental mode, allows for a range of queries and results display formats, making Elasticsearch more user-friendly, despite some limitations like the inability to execute JOIN statements. Additionally, the Translate API can convert SQL statements into Elasticsearch Query DSL, providing further flexibility in data querying and manipulation.