Construct a Sql block using With Clause to improve the performance

Question

I have got four diff parametrized cursor in my Pl/Sql Procedure. As the performance of the Procedure is very pathetic,so i have been asked to tune the Select statements used in those cursors.
So I am trying to use the With Clause in order to club all those four Select Statements.
I would appreciate if anybody can help me to construct the Sql Block using With Clause.
My DB version is..
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
PL/SQL Release 11.1.0.7.0 - Production
Four Diff cursors are defined below.
CURSOR all_iss (
      b_batch_end_date   IN   TIMESTAMP,
   IS
      SELECT isb.*
            FROM IMPLMN_STEP_BREKPN  isb
           , ISSUE iss
      WHERE isb.issue_id = iss.issue_id
       AND iss.issue_status_id  =  50738
       AND ewo_no IN
      (SELECT TO_CHAR(wo_no)
        FROM MGO_PLANT_AUDIT
       WHERE dml_status = 'U' OR dml_status = 'I')
      UNION ALL
      SELECT isb.*
       FROM IMPLMN_STEP_BREKPN  isb
        , ISSUE iss
       WHERE isb.issue_id = iss.issue_id
       AND iss.issue_status_id  =  50738
       AND CAST (isb.last_updt_timstm AS TIMESTAMP) >=
                                                              b_batch_end_date;
      CURSOR ewo_plant  ( p_ewo_no IN  IMPLMN_STEP_BREKPN.ewo_no%TYPE)
      IS
      SELECT DISTINCT wo_no ,
      plant_code
      FROM MGO_PLANT
      WHERE TO_CHAR(wo_no) = p_ewo_no;
      CURSOR iss_ewo_plnt (
      p_issue_id IN IMPLMN_STEP_BREKPN.issue_id%TYPE ,
      p_ewo_no IN IMPLMN_STEP_BREKPN.EWO_NO%TYPE,
      p_plnt_code IN IMPLMN_STEP_BREKPN.PLT_FACLTY_ID%TYPE)
      IS
      SELECT *
      FROM IMPLMN_STEP_BREKPN
      WHERE issue_id = p_issue_id
      AND ewo_no = p_ewo_no
      AND
      (plt_faclty_id = p_plnt_code
      OR
      plt_faclty_id IS NULL);
      CURSOR iss_ewo_plnt_count (
      p_issue_id IN IMPLMN_STEP_BREKPN.issue_id%TYPE ,
      p_ewo_no IN IMPLMN_STEP_BREKPN.EWO_NO%TYPE,
      p_plnt_code IN IMPLMN_STEP_BREKPN.PLT_FACLTY_ID%TYPE)
      IS
      SELECT COUNT(*)
      FROM IMPLMN_STEP_BREKPN
      WHERE issue_id = p_issue_id
      AND ewo_no = p_ewo_no
      AND
      (plt_faclty_id = p_plnt_code
      OR
      plt_faclty_id IS NULL);

Answer 1

Not tested. Some thing like below. i just made the queries as tables and given name as a,b,c and substituted columns for the parameters used in the 2nd cursor and third cursor. Try like this.
CURSOR all_iss (
b_batch_end_date IN TIMESTAMP,
IS
select a.*,b.*,c.* from
( SELECT isb.*
FROM IMPLMN_STEP_BREKPN isb
, ISSUE iss
WHERE isb.issue_id = iss.issue_id
AND iss.issue_status_id = 50738
AND ewo_no IN
(SELECT TO_CHAR(wo_no)
FROM MGO_PLANT_AUDIT
WHERE dml_status = 'U' OR dml_status = 'I')
UNION ALL
SELECT isb.*
FROM IMPLMN_STEP_BREKPN isb
, ISSUE iss
WHERE isb.issue_id = iss.issue_id
AND iss.issue_status_id = 50738
AND CAST (isb.last_updt_timstm AS TIMESTAMP) >=
b_batch_end_date) a,
( SELECT DISTINCT wo_no ,
plant_code
FROM MGO_PLANT
WHERE TO_CHAR(wo_no) = p_ewo_no) b,
( SELECT *
FROM IMPLMN_STEP_BREKPN
WHERE issue_id = p_issue_id
AND ewo_no = p_ewo_no
plt_faclty_id IS NULL) c
where b.wo_no = c.ewo_no and
c.issue_id = a.issue_id ;
vinodh
Edited by: Vinodh2 on Jul 11, 2010 12:03 PM