Hvad er forskellen på disse to forspørgelser?
*/mysql> select avg(windSpeed) from MillPerformance where millnumber = 10 and TO_DAYS('2002-11-01');
+-----------------+
| avg(windSpeed) |
+-----------------+
| 5.9193548387097 |
+-----------------+
1 row in set (0.01 sec)
mysql> select avg(windSpeed) from MillPerformance where millnumber = 10 and TO_DAYS(date) = TO_DAYS('2002-11-01');
+----------------+
| avg(windSpeed) |
+----------------+
| 5 |
+----------------+
1 row in set (0.01 sec)
mysql>
*/
Hvorfor for jeg to forskellige resultater?
