Data Types in SQL - Decimal
DECIMAL, NUMERIC, REAL, FLOAT and various other terms for various sets of rational numbers. When these key words are specified for the declared type of something, they are usually accompanied by precision and scale specifications. DECIMAL and NUMERIC are synonymous and are used for types with uniform scales, where the difference between any number and its immediate successor or predecessor is constant. For example, DECIMAL(5,2) consists of rational numbers with a precision of 5 (i.e., having at most 5 decimal digits) and a scale of one hundredth (i.e., 2 places of decimals), such as 372.57 and -1.00. (Note that SQL always uses the period "." as the decimal separator.)