Answer-What is 'query optimization' in DBMS?

The Query Optimizer part of the DBMS analyzes multiple possible execution plans for a given SQL query and selects the one with the lowest estimated cost IO, CPU, memory. It considers available indexes, table statistics, join algorithms nested loop, hash join, merge join, and cardinality estimates. Developers can influence optimization by creating appropriate indexes, updating statistics, rewriting queries, and using execution plan analysis tools EXPLAIN in MySQLPostgreSQL.

Question

What is 'query optimization' in DBMS?

A Rewriting SQL queries to use simpler syntax which are fast in execution

B The process by which the database engine automatically selects the most efficient execution plan for a query to minimize response time and resource usage

C Manually adding indexes to all database columns so that accessing data becomes fast

D Splitting large queries into multiple smaller queries so that the execution becomes faster and efficient

E Converting SQL queries to stored procedures for faster execution

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