STD()函數(shù)是用于返回表達的標準偏差。 這相當于服用表達的VARIANCE()的平方根。下面的例子計算CARS表列價格的標準差:
SQL>SELECT STD(PRICE) STD_DEVIATION FROM CARS; +---------------------------------------------------------+ | STD_DEVIATION | +---------------------------------------------------------+ | 7650.2146 | +---------------------------------------------------------+ 1 row in set (0.00 sec)