Understanding SQL Execution Internals and Join Methods in Oracle 19c & 23c AI
In this lecture, you will learn how Oracle executes SQL internally by exploring execution plan operators and join methods. You will gain a clear understanding of how the optimizer chooses execution strategies and how that affects performance.
Session highlights:
Understanding SQL execution plan operators (not SQL syntax operators)
How Oracle implements Nested Loop Joins
How Hash Joins work and when the optimizer prefers them
How Sort Merge Joins operate and their typical use cases
Concepts of driving table vs driven table
Join order and join method selection by the optimizer
Step-by-step approach to reading and interpreting an EXPLAIN PLAN
This lecture emphasizes practical execution plan analysis, enabling you to understand why Oracle chooses a particular operator or join method and how it impacts SQL performance.
Who should attend:
Oracle DBA beginners
SQL developers
Performance tuning learners seeking strong fundamentals in execution plan analysis