The PostgreSQL 9.0 Reference Manual - Volume 1A - SQL Language Reference by The PostgreSQL Global Development Group Paperback (6"x9"), 454 pages ISBN 9781906966041 RRP £14.95 ($19.95) Sales of this book support the PostgreSQL project! Get a printed copy>>>

PostgreSQL 9.0 Reference Manual Volume 1A Buy the book here! >>> support free software

6.1.1 Integer Types

The types smallint, integer, and bigint store whole numbers, that is, numbers without fractional components, of various ranges. Attempts to store values outside of the allowed range will result in an error.

The type integer is the common choice, as it offers the best balance between range, storage size, and performance. The smallint type is generally only used if disk space is at a premium. The bigint type should only be used if the integer range is insufficient, because the latter is definitely faster.

On very minimal operating systems the bigint type might not function correctly, because it relies on compiler support for eight-byte integers. On such machines, bigint acts the same as integer, but still takes up eight bytes of storage. (We are not aware of any modern platform where this is the case.)

SQL only specifies the integer types integer (or int), smallint, and bigint. The type names int2, int4, and int8 are extensions, which are also used by some other SQL database systems.