Save Exception or Bulk Exceptions in bulk collections

SET SERVEROUTPUT ON
DECLARE
  TYPE t_tab IS TABLE OF exception_test%ROWTYPE;

  l_tab          t_tab := t_tab();
  l_error_count  NUMBER;
  
  ex_dml_errors EXCEPTION;
  PRAGMA EXCEPTION_INIT(ex_dml_errors, -24381);
BEGIN
  -- Fill the collection.
  FOR i IN 1 .. 100 LOOP
    l_tab.extend;
    l_tab(l_tab.last).id := i;
  END LOOP;

  -- Cause a failure.
  l_tab(50).id := NULL;
  l_tab(51).id := NULL;
  
  EXECUTE IMMEDIATE 'TRUNCATE TABLE exception_test';

  -- Perform a bulk operation.
  BEGIN
    FORALL i IN l_tab.first .. l_tab.last SAVE EXCEPTIONS
      INSERT INTO exception_test
      VALUES l_tab(i);
  EXCEPTION
    WHEN ex_dml_errors THEN
      l_error_count := SQL%BULK_EXCEPTIONS.count;
      DBMS_OUTPUT.put_line('Number of failures: ' || l_error_count);
      FOR i IN 1 .. l_error_count LOOP
        DBMS_OUTPUT.put_line('Error: ' || i || 
          ' Array Index: ' || SQL%BULK_EXCEPTIONS(i).error_index ||
          ' Message: ' || SQLERRM(-SQL%BULK_EXCEPTIONS(i).ERROR_CODE));
      END LOOP;
  END;
END;
/

Number of failures: 2
Error: 1 Array Index: 50 Message: ORA-01400: cannot insert NULL into ()
Error: 2 Array Index: 51 Message: ORA-01400: cannot insert NULL into ()

PL/SQL procedure successfully completed.

Bulk Binding concept with Example

The FORALL syntax allows us to bind the contents of a collection to a single DML statement, allowing the DML to be run for each row in the collection without requiring a context switch each time. To test bulk binds using records we first create a test table.

CREATE TABLE forall_test (
  id           NUMBER(10),
  code         VARCHAR2(10),
  description  VARCHAR2(50));

ALTER TABLE forall_test ADD (
  CONSTRAINT forall_test_pk PRIMARY KEY (id));

ALTER TABLE forall_test ADD (
  CONSTRAINT forall_test_uk UNIQUE (code));

The following test compares the time taken to insert 10,000 rows using regular FOR..LOOP and a bulk bind.

SET SERVEROUTPUT ON
DECLARE
  TYPE t_forall_test_tab IS TABLE OF forall_test%ROWTYPE;

  l_tab    t_forall_test_tab := t_forall_test_tab();
  l_start  NUMBER;
  l_size   NUMBER            := 10000;
BEGIN
  -- Populate collection.
  FOR i IN 1 .. l_size LOOP
    l_tab.extend;

    l_tab(l_tab.last).id          := i;
    l_tab(l_tab.last).code        := TO_CHAR(i);
    l_tab(l_tab.last).description := 'Description: ' || TO_CHAR(i);
  END LOOP;

  EXECUTE IMMEDIATE 'TRUNCATE TABLE forall_test';

  -- Time regular inserts.
  l_start := DBMS_UTILITY.get_time;

  FOR i IN l_tab.first .. l_tab.last LOOP
    INSERT INTO forall_test (id, code, description)
    VALUES (l_tab(i).id, l_tab(i).code, l_tab(i).description);
  END LOOP;

  DBMS_OUTPUT.put_line('Normal Inserts: ' || 
                       (DBMS_UTILITY.get_time - l_start));
  
  EXECUTE IMMEDIATE 'TRUNCATE TABLE forall_test';

  -- Time bulk inserts.  
  l_start := DBMS_UTILITY.get_time;

  FORALL i IN l_tab.first .. l_tab.last
    INSERT INTO forall_test VALUES l_tab(i);

  DBMS_OUTPUT.put_line('Bulk Inserts  : ' || 
                       (DBMS_UTILITY.get_time - l_start));

  COMMIT;
END;
/
Normal Inserts: 305
Bulk Inserts  : 14

PL/SQL procedure successfully completed.

SQL>

Bulk Collect concept with Example

SET SERVEROUTPUT ON
DECLARE
  TYPE t_bulk_collect_test_tab IS TABLE OF bulk_collect_test%ROWTYPE;

  l_tab    t_bulk_collect_test_tab := t_bulk_collect_test_tab();
  l_start  NUMBER;
BEGIN
  -- Time a regular population.
  l_start := DBMS_UTILITY.get_time;

  FOR cur_rec IN (SELECT *
                  FROM   bulk_collect_test)
  LOOP
    l_tab.extend;
    l_tab(l_tab.last) := cur_rec;
  END LOOP;

  DBMS_OUTPUT.put_line('Regular (' || l_tab.count || ' rows): ' || 
                       (DBMS_UTILITY.get_time - l_start));
  
  -- Time bulk population.  
  l_start := DBMS_UTILITY.get_time;

  SELECT *
  BULK COLLECT INTO l_tab
  FROM   bulk_collect_test;

  DBMS_OUTPUT.put_line('Bulk    (' || l_tab.count || ' rows): ' || 
                       (DBMS_UTILITY.get_time - l_start));
END;
/
Regular (42578 rows): 66
Bulk    (42578 rows): 4

PL/SQL procedure successfully completed.

SQL>