MySQL中如何存储小数？

DECIMAL(yourTotalDigit,yourDigitsAfterDecimalPoint);

mysql> create table DecimalDemo
   -> (
   -> Amount DECIMAL(4,2)
   -> );
Query OK, 0 rows affected (0.47 sec)

mysql> insert into DecimalDemo values(123.4);
ERROR 1264 (22003): Out of range value for column 'Amount' at row 1

mysql> insert into DecimalDemo values(1234);
ERROR 1264 (22003): Out of range value for column 'Amount' at row 1

mysql> insert into DecimalDemo values(1234.56);
ERROR 1264 (22003): Out of range value for column 'Amount' at row 1

mysql> insert into DecimalDemo values(12.34);
Query OK, 1 row affected (0.13 sec)

mysql> insert into DecimalDemo values(12.4);
Query OK, 1 row affected (0.18 sec)

mysql> insert into DecimalDemo values(.2345);
Query OK, 1 row affected, 1 warning (0.18 sec)

mysql> insert into DecimalDemo values(1.234);
Query OK, 1 row affected, 1 warning (0.16 sec)

mysql> select *from DecimalDemo;

+--------+
| Amount |
+--------+
| 12.34  |
| 12.40  |
| 0.23   |
| 1.23   |
+--------+
4 rows in set (0.00 sec)