SEQUENCE Select within an SQL Query with an ORDER BY statement

Question

Does anyone know why you cannot use an ORDER BY statement within an SQL query when also selecting from a SEQUENCE? My query was selecting production data as a result of a filtered search. I want to take the results of the filtered search and create a transaction. I have a sequence for generating transaction numbers where I select NEXTVAL. Since I could possibly obtain multiple, yet distinct, rows based upon my search criteria, I wanted to use an ORDER BY statement to simplify and order the resulting row(s).
I was able to get the SQL select with SEQUENCE.NEXTVAL to work without the ORDER BY, so I know that my SQL is correct. Thanks in-advance.

Answer 1

Okay,
I understand. You want the sequence assigned first and the you want to ORDER BY. You
can do this using pipelined functions. See here:
CREATE OR REPLACE TYPE emp_rec_seq AS OBJECT (
   seq     NUMBER,
   ename   VARCHAR2 (20),
   job     VARCHAR2 (20),
   sal     NUMBER
CREATE OR REPLACE TYPE emp_tab_seq AS TABLE OF emp_rec_seq;
CREATE OR REPLACE FUNCTION get_emp_with_sequence
   RETURN emp_tab_seq PIPELINED
IS
   my_record   emp_rec_seq := emp_rec_seq (NULL, NULL, NULL, NULL);
BEGIN
   FOR c IN (SELECT dummy.NEXTVAL seq, ename, job, sal
               FROM emp)
   LOOP
      my_record.seq := c.seq;
      my_record.ename := c.ename;
      my_record.job := c.job;
      my_record.sal := c.sal;
      PIPE ROW (my_record);
   END LOOP;
   RETURN;
END get_emp_with_sequence;after that, you can do a select like this:
SELECT seq, ename, job, sal
  FROM TABLE (get_emp_with_sequence)
  order by enamewhich will get you this:
       SEQ ENAME                JOB                         SAL
      1053 BLAKE                MANAGER                    2850
      1054 CLARK                MANAGER                    2450
      1057 FORD                 ANALYST                    3000
      1062 JAMES                CLERK                       950
      1055 JONES                MANAGER                    2975
      1052 KING                 MANAGER                   20000
      1060 MARTIN               SALESMAN                   1250
      1063 MILLER               CLERK                      1300
      1064 DKUBICEK             MANAGER                   12000
      1056 SCOTT                ANALYST                    3000
      1058 SMITH                CLERK                       800
      1061 TURNER               SALESMAN                   1500
      1059 WARD                 SALESMAN                   1250Denes Kubicek
http://deneskubicek.blogspot.com/
http://htmldb.oracle.com/pls/otn/f?p=31517:1
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