POW( 数値X, 数値Y ) POWER( 数値X, 数値Y )
POW関数またはPOWER関数を使用することで数値Xの数値Y乗の数値を求めることができます。
mysql> SELECT POW( 10, 3 ); +--------------+ | POW( 10, 3 ) | +--------------+ | 1000 | +--------------+ 1 row in set (0.00 sec) mysql> SELECT POWER( 10, 3 ); +----------------+ | POWER( 10, 3 ) | +----------------+ | 1000 | +----------------+ 1 row in set (0.00 sec)
mysql> SELECT POW( 0.5, 3 ); +---------------+ | POW( 0.5, 3 ) | +---------------+ | 0.125 | +---------------+ 1 row in set (0.00 sec) mysql> SELECT POWER( 0.5, 3 ); +-----------------+ | POWER( 0.5, 3 ) | +-----------------+ | 0.125 | +-----------------+ 1 row in set (0.00 sec)
mysql> SELECT POW( -5, 4 ); +--------------+ | POW( -5, 4 ) | +--------------+ | 625 | +--------------+ 1 row in set (0.00 sec) mysql> SELECT POWER( -5, 4 ); +----------------+ | POWER( -5, 4 ) | +----------------+ | 625 | +----------------+ 1 row in set (0.00 sec)
mysql> SELECT POW( 10, -4 ); +---------------+ | POW( 10, -4 ) | +---------------+ | 0.0001 | +---------------+ 1 row in set (0.00 sec) mysql> SELECT POWER( 10, -4 ); +-----------------+ | POWER( 10, -4 ) | +-----------------+ | 0.0001 | +-----------------+ 1 row in set (0.00 sec)
文字を引数とした場合はNULLではなく0が返されます。
mysql> SELECT POW( 'a', 3 ); +---------------+ | POW( 'a', 3 ) | +---------------+ | 0 | +---------------+ 1 row in set (0.00 sec) mysql> SELECT POWER( 'a', 3 ); +-----------------+ | POWER( 'a', 3 ) | +-----------------+ | 0 | +-----------------+ 1 row in set (0.00 sec)