Index Hint无法使用主键

[AntTech_VWILWC]

举个例子，这里emp_department_ix如果是表的主键则执行计划里看到hint没有生效的，如果是一般的索引则是生效的，很奇怪
SELECT /+ INDEX (employees emp_department_ix)/ employee_id, department_id
FROM employees
WHERE department_id > 50;

[淇铭]

@AntTech_VWILWC

主键

hint /+index(test primary)/ 强制让它走主表。
explain extended SELECT /+ INDEX (employees primary) / employee_id, department_id
FROM employees
WHERE department_id > 50;