Floating-Point Types

Synopsis

Floating-point and fixed-point numbers are used to specify non-integer numbers. Different floating point datatypes represent different precision numbers.

Syntax

type_specification ::= { FLOAT | DOUBLE PRECISION | DECIMAL | DEC }

non_integer_floating_point_literal ::= non_integer_fixed_point_literal | "NaN" | "Infinity" | "-Infinity"

non_integer_fixed_point_literal ::= [ + | - ] { digit [ digit ...] '.' [ digit ...] | '.' digit [ digit ...] }

Where

• Columns of type FLOAT, DOUBLE PRECISION, DEC, or DECIMAL can be part of the PRIMARY KEY.
• non_integer_floating_point_literal is used for values of FLOAT, DOUBLE and DOUBLE PRECISION types.
• non_integer_fixed_point_literal is used for values of DECIMAL type.

Semantics

• Values of different floating-point and fixed-point datatypes are comparable and convertible to one another.
• Conversion from floating-point types into DECIMAL will raise an error for the special values NaN, Infinity, and -Infinity.
• The ordering for special floating-point values is defined as (in ascending order): -Infinity, all negative values in order, all positive values in order, Infinity, and NaN.
• Values of non-integer numeric datatypes are neither comparable nor convertible to integer although integers are convertible to them. This restriction will be removed.

See Also

Data Types