I am getting this "ORA-24381: error(s) in array DML error" in the code

Question

declare
TYPE RehrCD_TYP IS TABLE OF wk_rehr_entity_hierarchy.wk_rehr_cd%TYPE;
TYPE RehrParentCD_TYP IS TABLE OF wk_rehr_entity_hierarchy.wk_rehr_parent_cd%TYPE;
TYPE RehrESSPath_TYP IS TABLE OF wk_rehr_entity_hierarchy.wk_rehr_ess_path%TYPE;
L_levelRehrCD RehrCD_TYP;
L_levelParentCD RehrParentCD_TYP;
L_levelessPath RehrESSPath_TYP;
L_cItem VARCHAR2(50) := 'PRC_Update_Level :';
L_rows NUMBER DEFAULT 0;
CURSOR Update_Level_CUR
     IS
SELECT
wk_rehr_cd
,wk_rehr_parent_cd
,wk_rehr_ess_path
FROM
wk_rehr_entity_hierarchy
WHERE
wk_rehr_ess_path LIKE '/ENTITY/ACTIVITY_USD%';
BEGIN
OPEN Update_Level_CUR;
BEGIN
LOOP
FETCH Update_Level_CUR
BULK COLLECT INTO
L_levelRehrCD
,L_levelParentCD
,L_levelessPath
LIMIT 10000;
EXIT WHEN L_levelRehrCD.count = 0;
dbms_output.put_line(1);
FORALL i IN L_levelRehrCD.FIRST .. L_levelRehrCD.LAST SAVE EXCEPTIONS
UPDATE
wk_rehr_entity_hierarchy
SET
wk_rehr_ess_level = RPKG_Entity_Hierarchy.Get_Level(L_levelessPath(i))
WHERE
wk_rehr_cd = L_levelRehrCD(i)
AND wk_rehr_parent_cd = L_levelParentCD(i);
FOR j IN 1 .. L_levelRehrCD.COUNT
LOOP
L_rows := L_rows+ SQL%BULK_ROWCOUNT(j);
END LOOP;
END LOOP;
CLOSE Update_Level_CUR;
END;
end;
Please help me how to debug it?

Answer 1

Just get rid of the whole looping approach - it's slow, inefficient and you don't need it.
A single sql statement should always outperform looping code.
Also, try to bring the logic of RPKG_Entity_Hierarchy.Get_Level inline to the SQL.
If it's based on the column wk_rehr_ess_path then you might be able to use CONNECT BY or other methods to remove what is a bad practice and classic performance killer.
I was going to suggest a MERGE statement like this:
MERGE
INTO  wk_rehr_entity_hierarchy wk
USING (SELECT wk_rehr_cd
       ,      wk_rehr_parent_cd
       ,      RPKG_Entity_Hierarchy.Get_Level(wk_rehr_ess_path) lvl
       FROM   wk_rehr_entity_hierarchy
       WHERE  wk_rehr_ess_path LIKE '/ENTITY/ACTIVITY_USD%') xx
ON    (wk.wk_rehr_cd        = xx.wk_rehr_cd
AND    wk.wk_rehr_parent_cd = xx.wk_rehr_parent_cd)
WHEN MATCHED THEN
       UPDATE
       SET    wk_rehr_ess_level = xx.lvl;But then I realised you're selecting from and updating the same table.
Are you sure this isn't achievable in just a single update?
UPDATE wk_rehr_entity_hierarchy
SET    wk_rehr_ess_level = RPKG_Entity_Hierarchy.Get_Level(wk_rehr_ess_path)
WHERE  wk_rehr_ess_path LIKE '/ENTITY/ACTIVITY_USD%';And then you can bring that function logic inline - much more efficient.