クエリのパフォーマンスの違いpl/sqlforallinsertとplainSQLinsert

問題に関するいくつかの実験データ（Oracle 9.2）

一括収集

DECLARE 
  TYPE t_number_table IS TABLE OF NUMBER;
  v_tab t_number_table;
BEGIN
  SELECT ROWNUM
  BULK COLLECT INTO v_tab
  FROM dual
  CONNECT BY LEVEL < 100000;

  FORALL i IN 1..v_tab.COUNT
    INSERT INTO test VALUES (v_tab(i));
END;
/
-- 2.6 sec

挿入

-- test table 
CREATE global TEMPORARY TABLE test (id number)
ON COMMIT preserve ROWS;

BEGIN
  INSERT INTO test
  SELECT ROWNUM FROM dual
  CONNECT BY LEVEL < 100000;
END;
/
-- 1.4 sec

ダイレクトパス挿入 http://download.oracle.com/docs /cd/B10500_01/server.920/a96524/c21dlins.htm

BEGIN
  INSERT /*+ append */ INTO test
  SELECT ROWNUM FROM dual
  CONNECT BY LEVEL < 100000;
END;
/
-- 1.2 sec