先查詢測試表格(tmp01)的相關資料,會使用模糊查詢是因為我在實驗上發現如果有INDEX,它會被載入Buffer Cache,而不會是Table
SQL> select object_id,object_name from dba_objects where object_name like upper('%tmp_01%');
OBJECT_ID OBJECT_NAME
SELECT col1, col2, count(*) FROM t1 GROUP BY col1, col2 HAVING count(*) > 1;
SELECT * FROM t1 a where a.rowid > (SELECT min(b.rowid) FROM t1 b WHERE b.col1=a.col1);