By default, the scale for a DECIMAL type is 0, which means the DECIMAL data type mimics an integer type.
默认情况下,decimal类型的刻度为0,这意味着DECIMAL数据类型模拟了整数类型。
2
We need to be accurate to two decimal places (e.g. in a simple accounting package), scale everything up by 100, and convert it back to floating point as late as possible.