Network Address Type Functions
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
| Operator | Description | Usage |
|---|---|---|
| < | Less than | inet '192.168.1.5' < inet '192.168.1.6' |
| <= | Less than or equal | inet '192.168.1.5' <= inet '192.168.1.5' |
| = | Equals | inet '192.168.1.5' = inet '192.168.1.5' |
| >= | Greater or equal | inet '192.168.1.5' >= inet '192.168.1.5' |
| > | Greater | inet '192.168.1.5' > inet '192.168.1.4' |
| <> | Not equal | inet '192.168.1.5' <> inet '192.168.1.4' |
| << | is contained within | inet '192.168.1.5' << inet '192.168.1/24' |
| <<= | is contained within or equals | inet '192.168.1/24' <<= inet '192.168.1/24' |
| >> | contains | inet'192.168.1/24' >> inet '192.168.1.5' |
| >>= | contains or equals | inet '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
| Function | Returns | Description | Example | Result |
|---|---|---|---|---|
broadcast(inet) | inet | broadcast address for network | broadcast('192.168.1.5/24') | 192.168.1.255/24 |
host(inet) | text | extract IP address as text | host('192.168.1.5/24') | 192.168.1.5 |
masklen(inet) | integer | extract netmask length | masklen('192.168.1.5/24') | 24 |
set_masklen(inet,integer) | inet | set netmask length for inet value | set_masklen('192.168.1.5/24',16) | 192.168.1.5/16 |
netmask(inet) | inet | construct netmask for network | netmask('192.168.1.5/24') | 255.255.255.0 |
network(inet) | cidr | extract network part of address | network('192.168.1.5/24') | 192.168.1.0/24 |
text(inet) | text | extract IP address and masklen as text | text(inet '192.168.1.5') | 192.168.1.5/32 |
abbrev(inet) | text | extract abbreviated display as text | abbrev(cidr '10.1.0.0/16') | 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
| Function | Returns | 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.