EXPLAIN Query Plan in MySQL

What is EXPLAIN?

Example

EXPLAIN SELECT * FROM students WHERE marks > 80;

Look at the type and key columns: type=ALL means a full table scan (slow); a named key means an index is used (fast).

Summary

• EXPLAIN reveals the query plan: indexes used and rows scanned.
• type=ALL = full scan (add an index); a key = index used.

EXPLAIN क्या है?

Example

EXPLAIN SELECT * FROM students WHERE marks > 80;

type और key columns देखें: type=ALL मतलब full table scan (धीमा); named key मतलब index use हो रहा (तेज़)।

सारांश

• EXPLAIN query plan दिखाता है: indexes और scan की rows।
• type=ALL = full scan (index जोड़ें); key = index use हो रहा।