v.20.6New Feature

Added Initial Implementation of EXPLAIN Query in ClickHouse

Added an initial implementation of EXPLAIN query. Syntax: EXPLAIN SELECT .... This fixes #1118. #11873 (Nikolai Kochetov).
Added an initial implementation of the EXPLAIN query for ClickHouse, allowing users to analyze and understand query execution plans by running EXPLAIN SELECT ....

Why it matters

The EXPLAIN query helps users by providing insight into how ClickHouse executes a query, enabling better query optimization and debugging by showing the query plan before actual execution. This solves the need for visibility into query processing addressed in issue #1118.

How to use it

To use this feature, prepend the keyword EXPLAIN before your query. For example:

EXPLAIN SELECT * FROM table_name WHERE condition;