{es-sql} is an X-Pack component that allows SQL-like queries to be executed in real-time against {es}.
Whether using the REST interface, command-line or JDBC, any client can use SQL to search and aggregate data
_natively_ inside {es}.
One can think of {es-sql} as a _translator_, one that understands both SQL and {es} and makes it easy to read and process data in real-time, at scale by leveraging {es} capabilities.
{es-sql} is built from the ground up for {es}. Each and every query is efficiently executed against the relevant nodes according to the underlying storage.
No external parts::
No need for additional hardware, processes, runtimes or libraries to query {es}; {es-sql} eliminates extra moving parts by running _inside_ the {es} cluster.
Lightweight and efficient::
{es-sql} does not abstract {es} and its search capabilities - on the contrary, it embrases and exposes to SQL to allow proper full-text search, in real-time, in the same declarative, succint fashion.