Oracle存储过程引用多表查询怎么返回结果数据
时间: 2023-07-13 20:17:45 浏览: 201
在Oracle存储过程中引用多表查询可以通过游标返回结果数据。具体操作如下:
1. 定义一个游标类型,该游标类型包含存储过程需要返回的数据,例如:
```
TYPE result_cursor IS REF CURSOR RETURN employees.employee_id%TYPE;
```
2. 在存储过程中使用OPEN-FOR语句打开游标,并将查询结果存储到游标中,例如:
```
PROCEDURE get_employee_info(p_employee_id IN employees.employee_id%TYPE, p_result OUT result_cursor)
AS
BEGIN
OPEN p_result FOR
SELECT e.employee_id, e.first_name, e.last_name, d.department_name
FROM employees e, departments d, employees_departments ed
WHERE e.employee_id = ed.employee_id
AND d.department_id = ed.department_id
AND e.employee_id = p_employee_id;
END;
```
3. 调用存储过程时,将OUT参数设置为游标类型,并使用FETCH语句获取查询结果,例如:
```
DECLARE
v_result result_cursor;
v_employee_id employees.employee_id%TYPE;
v_first_name employees.first_name%TYPE;
v_last_name employees.last_name%TYPE;
v_department_name departments.department_name%TYPE;
BEGIN
get_employee_info(100, v_result);
LOOP
FETCH v_result INTO v_employee_id, v_first_name, v_last_name, v_department_name;
EXIT WHEN v_result%NOTFOUND;
DBMS_OUTPUT.PUT_LINE(v_employee_id || ' ' || v_first_name || ' ' || v_last_name || ' ' || v_department_name);
END LOOP;
CLOSE v_result;
END;
```
通过上述方式,就可以在Oracle存储过程中引用多表查询,并返回结果数据。