Bulk collect workaround for memory bug

Datetime:2016-08-23 02:23:33          Topic: SQL  Oracle           Share

A coworker passed a test script on to me that was failing with the following memory error:

ORA-04030: out of process memory when trying to allocate 4088 bytes (PLS CGA hp,pdzgM64_New_Link)

The error occurred when initializing a PL/SQL table variable with 7500 objects. Here is my sanitized version of the code:

CREATE OR REPLACE TYPE ARRAY_ELEMENT
AS
  OBJECT
  (
    n1 NUMBER,
    n2 NUMBER,
    n3 NUMBER,
    n4 NUMBER );
/

CREATE OR REPLACE TYPE MY_ARRAY
IS
  TABLE OF ARRAY_ELEMENT;
/

DECLARE
  MY_LIST MY_ARRAY;
BEGIN
  MY_LIST := MY_ARRAY(
    ARRAY_ELEMENT(1234,5678,1314,245234),
    ARRAY_ELEMENT(1234,5678,1314,245234),
    ARRAY_ELEMENT(1234,5678,1314,245234),
...
    ARRAY_ELEMENT(1234,5678,1314,245234),
    ARRAY_ELEMENT(1234,5678,1314,245234)
  );

The real code had different meaningful constants for each entry in the table. Here is the error:

8004      ARRAY_ELEMENT(1234,5678,1314,245234)
8005    );
8006  
8007  END;
8008  /
DECLARE
*
ERROR at line 1:
ORA-04030: out of process memory when trying to allocate 4088 bytes 
(PLS CGA hp,pdzgM64_New_Link)


Elapsed: 00:02:51.31

I wrapped the error code manually so it would fit on the page.

The solution looks like this:

create table MY_OBJECTS
  (
    o ARRAY_ELEMENT );

DECLARE
  MY_LIST MY_ARRAY;
BEGIN
 MY_LIST := MY_ARRAY( );
  
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
...
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
 insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));

 commit;
  
 SELECT o
   BULK COLLECT INTO MY_LIST
   FROM MY_OBJECTS; 

END;
/

Here is what the successful run looks like:

8004    insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
8005    insert into MY_OBJECTS values(ARRAY_ELEMENT(1234,5678,1314,245234));
8006  
8007    commit;
8008  
8009    SELECT o
8010      BULK COLLECT INTO MY_LIST
8011      FROM MY_OBJECTS;
8012  
8013  END;
8014  /

PL/SQL procedure successfully completed.

Elapsed: 00:00:21.36
SQL>

There is an Oracle document about this bug:

ORA-4030 (PLSQL Opt Pool,pdziM01_Create: New Set), ORA-4030 (PLS CGA hp,pdzgM64_New_Link) (Doc ID 1551115.1)

It doesn’t have using bulk collect as a work around. My situation could be only useful in very specific cases but I thought it was worth sharing it.

Here are my scripts and their logs:zip

Bobby





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