This page in other versions: 9.1 / 9.2 / 9.3 / 9.4 / current (9.5)  |  Development versions: devel  |  Unsupported versions: 7.1 / 7.2 / 7.3 / 7.4 / 8.0 / 8.1 / 8.2 / 8.3 / 8.4 / 9.0

9.12. Network Address Functions and Operators

Table 9-34 shows the operators available for the cidr and inet types. The operators <<, <<=, >>, >>=, and && test for subnet inclusion. They consider only the network parts of the two addresses (ignoring any host part) and determine whether one network is identical to or a subnet of the other.

Table 9-34. cidr and inet Operators

Operator Description Example
< is less than inet '' < inet ''
<= is less than or equal inet '' <= inet ''
= equals inet '' = inet ''
>= is greater or equal inet '' >= inet ''
> is greater than inet '' > inet ''
<> is not equal inet '' <> inet ''
<< is contained by inet '' << inet '192.168.1/24'
<<= is contained by or equals inet '192.168.1/24' <<= inet '192.168.1/24'
>> contains inet '192.168.1/24' >> inet ''
>>= contains or equals inet '192.168.1/24' >>= inet '192.168.1/24'
&& contains or is contained by inet '192.168.1/24' && inet ''
~ bitwise NOT ~ inet ''
& bitwise AND inet '' & inet ''
| bitwise OR inet '' | inet ''
+ addition inet '' + 25
- subtraction inet '' - 36
- subtraction inet '' - inet ''

Table 9-35 shows the functions available for use with the cidr and inet types. The abbrev, host, and text functions are primarily intended to offer alternative display formats.

Table 9-35. cidr and inet Functions

Function Return Type Description Example Result
abbrev(inet) text abbreviated display format as text abbrev(inet '')
abbrev(cidr) text abbreviated display format as text abbrev(cidr '') 10.1/16
broadcast(inet) inet broadcast address for network broadcast('')
family(inet) int extract family of address; 4 for IPv4, 6 for IPv6 family('::1') 6
host(inet) text extract IP address as text host('')
hostmask(inet) inet construct host mask for network hostmask('')
masklen(inet) int extract netmask length masklen('') 24
netmask(inet) inet construct netmask for network netmask('')
network(inet) cidr extract network part of address network('')
set_masklen(inet, int) inet set netmask length for inet value set_masklen('', 16)
set_masklen(cidr, int) cidr set netmask length for cidr value set_masklen(''::cidr, 16)
text(inet) text extract IP address and netmask length as text text(inet '')
inet_same_family(inet, inet) boolean are the addresses from the same family? inet_same_family('', '::1') false
inet_merge(inet, inet) cidr the smallest network which includes both of the given networks inet_merge('', '')

Any cidr value can be cast to inet implicitly or explicitly; therefore, the functions shown above as operating on inet also work on cidr values. (Where there are separate functions for inet and cidr, it is because the behavior should be different for the two cases.) Also, it is permitted to cast an inet value to cidr. When this is done, any bits to the right of the netmask are silently zeroed to create a valid cidr value. In addition, you can cast a text value to inet or cidr using normal casting syntax: for example, inet(expression) or colname::cidr.

Table 9-36 shows the functions available for use with the macaddr type. The function trunc(macaddr) returns a MAC address with the last 3 bytes set to zero. This can be used to associate the remaining prefix with a manufacturer.

Table 9-36. macaddr Functions

Function Return Type Description Example Result
trunc(macaddr) macaddr set last 3 bytes to zero trunc(macaddr '12:34:56:78:90:ab') 12:34:56:00:00:00

The macaddr type also supports the standard relational operators (>, <=, etc.) for lexicographical ordering, and the bitwise arithmetic operators (~, & and |) for NOT, AND and OR.

Add Comment

Please use this form to add your own comments regarding your experience with particular features of PostgreSQL, clarifications of the documentation, or hints for other users. Please note, this is not a support forum, and your IP address will be logged. If you have a question or need help, please see the faq, try a mailing list, or join us on IRC. Note that submissions containing URLs or other keywords commonly found in 'spam' comments may be silently discarded. Please contact the webmaster if you think this is happening to you in error.

Proceed to the comment form.

Privacy Policy | About PostgreSQL
Copyright © 1996-2016 The PostgreSQL Global Development Group