v long_query_time 2002-01-21 18:12:12
v LOG(X) 2002-01-21 18:12:12
v PI() 2002-01-21 18:12:12
v ROUND(X) 2002-01-21 18:12:12
v FLOOR(X) 2002-01-21 18:12:12
v / 2002-01-21 18:12:12
v LAST_INSERT_ID( 2002-01-21 18:12:12
v case 2002-01-21 18:12:12
v OR || 逻辑或 2002-01-21 18:12:12
v >> 右移 2002-01-21 18:12:12