6.10. Network Address Type Functions

Table 6-23 shows the operators available for the inet and cidr types. The operators <<, <<=, >>, >>= test for subnet inclusion: they consider only the network parts of the two addresses, ignoring any host part, and determine whether one network part is identical to or a subnet of the other.

Table 6-23. cidr and inet Operators

< Less thaninet '' < inet ''
<= Less than or equalinet '' <= inet ''
= Equalsinet '' = inet ''
>= Greater or equalinet '' >= inet ''
> Greaterinet '' > inet ''
<> Not equalinet '' <> inet ''
<< is contained withininet '' << inet '192.168.1/24'
<<= is contained within or equalsinet '192.168.1/24' <<= inet '192.168.1/24'
>> containsinet'192.168.1/24' >> inet ''
>>= contains or equalsinet '192.168.1/24' >>= inet '192.168.1/24'

Table 6-24 shows the functions available for use with the inet and cidr types. The host(), text(), and abbrev() functions are primarily intended to offer alternative display formats. You can cast a text field to inet using normal casting syntax: inet(expression) or colname::inet.

Table 6-24. cidr and inet Functions

broadcast(inet)inetbroadcast address for networkbroadcast('')
host(inet)textextract IP address as texthost('')
masklen(inet)integerextract netmask lengthmasklen('')24
set_masklen(inet,integer)inetset netmask length for inet valueset_masklen('',16)
netmask(inet)inetconstruct netmask for networknetmask('')
network(inet)cidrextract network part of addressnetwork('')
text(inet)textextract IP address and masklen as texttext(inet '')
abbrev(inet)textextract abbreviated display as textabbrev(cidr '')10.1/16

Table 6-25 shows the functions available for use with the mac type. The function trunc(macaddr) returns a MAC address with the last 3 bytes set to 0. This can be used to associate the remaining prefix with a manufacturer. The directory contrib/mac in the source distribution contains some utilities to create and maintain such an association table.

Table 6-25. macaddr Functions

trunc(macaddr)macaddrset last 3 bytes to zerotrunc(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.