BP022
Published 24 N 2017
MONEY/SMALLMONEY datatype is used
The MONEY data type confuses the storage of data values with their display, though its name clearly suggests the sort of data it holds. It is proprietary to SQL Server and allows you to specify monetary values preceded by a currency symbol, but SQL Server doesn’t store any currency information at all with the actual numeric values, so the purpose of this is unclear.
It has limited precision; the underlying type is a BIGINT or, in the case of SMALLMONEY, an INT, so you can unintentionally get a loss of precision due to rounding errors. While simple addition or subtraction is fine, more complicated calculations that can be done for financial reports can show errors. Although the MONEY datatype generally takes less storage, and takes less bandwidth when sent over networks, via TDS, it is generally far better to use a data type such as the DECIMAL or NUMERIC type, which is less likely to suffer from rounding errors or scale overflow.