9.12. Network Address Functions and Operators
Table 9.36 shows the operators available for thecidr
andinet
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 9.36. cidr
andinet
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 by | inet '192.168.1.5' << 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 '192.168.1.5' |
>>= | contains or equals | inet '192.168.1/24' >>= inet '192.168.1/24' |
&& | contains or is contained by | inet '192.168.1/24' && inet '192.168.1.80/28' |
~ | 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 9.37 shows the functions available for use with thecidr
andinet
types. Theabbrev
,host
, andtext
functions are primarily intended to offer alternative display formats.
Table 9.37. cidr
andinet
Functions
Anycidr
value can be cast toinet
implicitly or explicitly; therefore, the functions shown above as operating oninet
also work oncidr
values. (Where there are separate functions forinet
andcidr
, it is because the behavior should be different for the two cases.) Also, it is permitted to cast aninet
value tocidr
. When this is done, any bits to the right of the netmask are silently zeroed to create a validcidr
value. In addition, you can cast a text value toinet
orcidr
using normal casting syntax: for example,inet(
orexpression
)
.colname
::cidr
Table 9.38 shows the functions available for use with themacaddr
type. The function
returns a MAC address with the last 3 bytes set to zero. This can be used to associate the remaining prefix with a manufacturer.trunc(
macaddr
)
Table 9.38. macaddr
Functions
Themacaddr
type also supports the standard relational operators (>
,<=
, etc.) for lexicographical ordering, and the bitwise arithmetic operators (~
,&
and|
) for NOT, AND and OR.