大量的游标，一个流水线功能

Question

我有这样的代码：

CREATE OR REPLACE TYPE person_typ AS OBJECT (ssn NUMBER(9), 
name VARCHAR2(30), address VARCHAR2(100));

CREATE OR REPLACE TYPE t_tab AS TABLE OF person_typ;

CREATE OR REPLACE FUNCTION my_pipe(p_in VARCHAR2) RETURN t_tab PIPELINED IS
     rec person_typ;

     CURSOR cur1 IS
          SELECT ssn, name, address FROM /* ... complex query */

     CURSOR cur2 IS
          SELECT ssn, name, address FROM /* ... complex query */

     CURSOR cur3 IS
          SELECT ssn, name, address FROM /* ... complex query */

     CURSOR cur4 IS
          SELECT ssn, name, address FROM /* ... complex query */

     CURSOR cur5 IS
          SELECT ssn, name, address FROM /* ... complex query */
BEGIN
    FOR cur IN cur1 LOOP
        rec := r_inc(cur.ssn, cur.name, cur.address);
        PIPE ROW(rec);
    END LOOP; 

    FOR cur IN cur2 LOOP
        rec := r_inc(cur.ssn, cur.name, cur.address);
        PIPE ROW(rec);
    END LOOP; 

    FOR cur IN cur3 LOOP
        rec := r_inc(cur.ssn, cur.name, cur.address);
        PIPE ROW(rec);
    END LOOP; 

    FOR cur IN cur4 LOOP
        rec := r_inc(cur.ssn, cur.name, cur.address);
        PIPE ROW(rec);
    END LOOP; 

    FOR cur IN cur5 LOOP
        rec := r_inc(cur.ssn, cur.name, cur.address);
        PIPE ROW(rec);
    END LOOP; 
END;

我的问题是我的流水线函数太丑了-我必须有五个游标（这与我无关），但是我不想有五个for循环。 我宁愿只有一个循环和一个PIPE ROW（rec）语句...有什么方法可以将结果连接到一个集合中，然后对其进行迭代？

Answer 1

嗯，如何使用union all并只有一个光标的联合？

 CURSOR cur1 IS
      SELECT ssn, name, address FROM /* ... complex query */
      UNION ALL
      SELECT ssn, name, address FROM /* ... complex query */
      UNION ALL
      SELECT ssn, name, address FROM /* ... complex query */
      UNION ALL
      SELECT ssn, name, address FROM /* ... complex query */
      UNION ALL
      SELECT ssn, name, address FROM /* ... complex query */