统计数据的SQL例子

/* Formatted on 2011/06/08 17:58 (Formatter Plus v4.8.8) */SELECT     (SELECT 1 + 1 FROM DUAL) + (SELECT 2 + 2 FROM DUAL) col1,    3 + 4 col2,    34 col3  FROM DUAL;/* result      COL1       COL2       COL3---------- ---------- ----------         6          7         341 row selected.*/