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Table 9-31 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 part is identical to or a subnet of the other.
Table 9-31. cidr and inet Operators
| Operator | Description | Example |
|---|---|---|
| < | is less than | inet '192.168.1.5' < inet '192.168.1.6' |
| <= | is 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' |
| >= | is greater or equal | inet '192.168.1.5' >= inet '192.168.1.5' |
| > | is greater than | inet '192.168.1.5' > inet '192.168.1.4' |
| <> | is 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' |
| ~ | bitwise NOT | ~ inet '192.168.1.6' |
| & | bitwise AND | inet '192.168.1.6' & inet '0.0.0.255' |
| | | bitwise OR | inet '192.168.1.6' | inet '0.0.0.255' |
| + | addition | inet '192.168.1.6' + 25 |
| - | subtraction | inet '192.168.1.43' - 36 |
| - | subtraction | inet '192.168.1.43' - inet '192.168.1.19' |
Table 9-32
shows the functions available for use with the
cidr
and
inet
types. The
host
,
text
, and
abbrev
functions are primarily intended to offer alternative display formats.
Table 9-32. cidr and inet Functions
| Function | Return Type | Description | Example | Result |
|---|---|---|---|---|
abbrev
(
inet
)
|
text | abbreviated display format as text | abbrev(inet '10.1.0.0/16') | 10.1.0.0/16 |
abbrev
(
cidr
)
|
text | abbreviated display format as text | abbrev(cidr '10.1.0.0/16') | 10.1/16 |
broadcast
(
inet
)
|
inet | broadcast address for network | broadcast('192.168.1.5/24') | 192.168.1.255/24 |
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('192.168.1.5/24') | 192.168.1.5 |
hostmask
(
inet
)
|
inet | construct host mask for network | hostmask('192.168.23.20/30') | 0.0.0.3 |
masklen
(
inet
)
|
int | extract netmask length | masklen('192.168.1.5/24') | 24 |
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 |
set_masklen
(
inet
,
int
)
|
inet | set netmask length for inet value | set_masklen('192.168.1.5/24', 16) | 192.168.1.5/16 |
set_masklen
(
cidr
,
int
)
|
cidr | set netmask length for cidr value | set_masklen('192.168.1.0/24'::cidr, 16) | 192.168.0.0/16 |
text
(
inet
)
|
text | extract IP address and netmask length as text | text(inet '192.168.1.5') | 192.168.1.5/32 |
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 9-33
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 9-33. 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.