Learning PostgreSQL 11 - Third Edition

Numeric types

The following table shows the various numeric types:

Name	Comments	Size	Range
smallint	SQL equivalent: Int2	2 bytes	-32,768 to +32,767.
integer	SQL equivalent: Int4 Integer is an alias for INT.	4 bytes	-2,147,483,648 to +2,147,483,647.
bigint	SQL equivalent: Int8 8 bytes	8 bytes	-9,223,372,036,854,775,808 to +9,223,372,036,854,775,807.
numeric or decimal	No difference in PostgreSQL	Variable	Up to 131,072 digits before the decimal point; up to 16,383 digits after the decimal point.
real	Special values: Infinity, Infinity, NaN	4 bytes	Platform-dependent, at least six-digit precision. Often, the range is 1E-37 to 1E+37.
double precision	Special values: Infinity, ...