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Floating point types

We support standard IEEE 754 floating point types.

double is a 64-bit standard FP value. Accepted synonyms are float8 and float64.

float is a 32-bit standard FP value. Accepted synonyms are float4, and float32.

Floating point values include special values, such as NaN (not a number), -Infinity, and -Infinity. An alternative spelling for -Infinity is -inf, and an alternative spelling for Infinity is inf, and an alternative spelling for 'NaN' is 'nan'. When written as SQL literals, these values have to be surrounded by simple quotes: 'inf'. Please note that these strings are case-sensitive and spaces are ignored.

Infinity plus any finite value equals Infinity, as does Infinity plus Infinity. Infinity minus Infinity yields NaN.

NaN (not a number) value is used to represent undefined results. An operation with a NaN input yields NaN. The only exception is when the operation's output does not depend on the NaN value: an example is NaN raised to the zero power yields one.

In sorting order NaN is considered greater than all other values.

The legal operations are + (plus, unary and binary), - (minus, unary and binary), * (multiplication), / (division). (modulus).

Division or modulus by zero return NaN.

Casting a string to a floating-point value will produce the value 0 when parsing fails.

Casting a value that is out of the supported range to a floating point type will produce a value that is inf or -inf.

Please note that numeric values with a decimal point have the decimal type by default. To write a floating-point literal you have to include the e for exponent using the following grammar:

digits.digits[e[+-]digits]

[digits].digits[e[+-]digits]

Alternatively, you can use an explicit cast:

REAL '1.23'  -- string style
1.23::REAL   -- PostgreSQL style

Predefined functions on Floating-point Values

ABS(value) absolute value
CEIL(value) Ceiling function: nearest integer value greater than or equal to argument (result is a floating point value)
FLOOR(value) Floor function: nearest integer value less than or equal to argument (result is a floating point value)
POWER(BASE, EXPONENT) The power function, raising BASE to the power EXPONENT
SQRT(value) Square root of value. Produces a runtime error for negative values.
LN(value) The natural logarithm of value. Produces a runtime error for values less than or equal to zero.
LOG10(value) The logarithm base 10 of value. Produces a runtime error for values less than or equal to zero.
SIN(value) The sine of value as radians. sin only supports argument of type double, so all other types are cast to double. Returns a double.
COS(value) The cosine of value as radians. cos only supports argument of type double, so all other types are cast to double. Returns a double.