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Section 3: Understanding The Optimizer > Execution Plan Operations
Execution Plan Operations
As you progress through this course and gain experience in understanding the internal execution of a SQL statement, we will eventually discuss in exhaustive detail the various operations found within an execution plan. But for now, consider some examples of operations which you should start to scrutinize as you find these within the SQL statements you are monitoring:
- Access methods
- Join methods
- Data operations
Access Methods
The rows highlighted within the execution plan shown here indicate the access method for each table.
As you have no doubt already noticed and recognized, the access method TABLE ACCESS FULL indicates a Full Table Scan where block within the table is fetched sequentially. As each block is read, individual rows are examined looking for last name values equal to ‘Smith’.