Oracle index prompt Parsing

When the Oracle index prompts parsing hints, in some cases, we may specify a full set of hints to ensure that the optimizer produces the optimal execution plan. Oracle index prompt, oracle index prompt, oracle index tips, oracle index OPTIMIZATION, Oracle index prompt. Www.2cto.com indicates the optimizer method and target hints: ALL_ROWS-cost-based optimizer, FIRST_ROWS (n)-cost-based optimizer, CHOOSE with response time as the target -- SELECT different optimizer RULE based on statistical information -- use the RULE-based optimizer SELECT/* + FIRST_ROWS (10) */employee_id, last_name, salary, job_id FROM employeesWHERE region = 20; SELECT/* + CHOOSE */employee_id, last_name, salary, job_idFROM employees WHERE employee_id = 7566; SELECT/* + RULE */employee_id, last_name, salary, job_idFROM employees WHERE employee_id = 7566;