Rule Based Optimizer   «Prev 

Rule-based Optimizer Process

1) The rule-based optimizer parses the syntax of the SQL to ensure thta it is valid

2. Once validated, the SQL examines the order of the table names in the FROM clause. The last table in the FROM clause becomes the driving table.

3. The rule-based optimizer next examine the conditions in the statement's WHERE clause to determine which access paths are available

4.The optimizer then chooses the most highly ranked available access ptah from the acces path hierarchy.