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ipv4_compare()

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Compares two IPv4 strings. The two IPv4 strings are parsed and compared while accounting for the combined IP-prefix mask calculated from argument prefixes, and the optional PrefixMask argument.

ipv4_compare("127.0.0.1", "127.0.0.1") == 0
ipv4_compare('192.168.1.1', '192.168.1.255') < 0
ipv4_compare('192.168.1.1/24', '192.168.1.255/24') == 0
ipv4_compare('192.168.1.1', '192.168.1.255', 24) == 0

Syntax

ipv4_compare(Expr1, Expr2[ ,PrefixMask])

Arguments

  • Expr1, Expr2: A string expression representing an IPv4 address. IPv4 strings can be masked using IP-prefix notation.
  • PrefixMask: An integer from 0 to 32 representing the number of most-significant bits that are taken into account.

IP-prefix notation

IP addresses can be defined with IP-prefix notation using a slash (/) character. The IP address to the LEFT of the slash (/) is the base IP address. The number (1 to 32) to the RIGHT of the slash (/) is the number of contiguous 1 bit in the netmask.

For example, 192.168.2.0/24 will have an associated net/subnetmask containing 24 contiguous bits or 255.255.255.0 in dotted decimal format.

Returns

  • 0: If the long representation of the first IPv4 string argument is equal to the second IPv4 string argument
  • 1: If the long representation of the first IPv4 string argument is greater than the second IPv4 string argument
  • -1: If the long representation of the first IPv4 string argument is less than the second IPv4 string argument
  • null: If conversion for one of the two IPv4 strings wasn't successful.

Examples: IPv4 comparison equality cases

Compare IPs using the IP-prefix notation specified inside the IPv4 strings

datatable(ip1_string:string, ip2_string:string)
[
 '192.168.1.0',    '192.168.1.0',       // Equal IPs
 '192.168.1.1/24', '192.168.1.255',     // 24 bit IP-prefix is used for comparison
 '192.168.1.1',    '192.168.1.255/24',  // 24 bit IP-prefix is used for comparison
 '192.168.1.1/30', '192.168.1.255/24',  // 24 bit IP-prefix is used for comparison
]
| extend result = ipv4_compare(ip1_string, ip2_string)
ip1_string ip2_string result
192.168.1.0 192.168.1.0 0
192.168.1.1/24 192.168.1.255 0
192.168.1.1 192.168.1.255/24 0
192.168.1.1/30 192.168.1.255/24 0

Compare IPs using IP-prefix notation specified inside the IPv4 strings and as additional argument of the ipv4_compare() function

datatable(ip1_string:string, ip2_string:string, prefix:long)
[
 '192.168.1.1',    '192.168.1.0',   31, // 31 bit IP-prefix is used for comparison
 '192.168.1.1/24', '192.168.1.255', 31, // 24 bit IP-prefix is used for comparison
 '192.168.1.1',    '192.168.1.255', 24, // 24 bit IP-prefix is used for comparison
]
| extend result = ipv4_compare(ip1_string, ip2_string, prefix)
ip1_string ip2_string prefix result
192.168.1.1 192.168.1.0 31 0
192.168.1.1/24 192.168.1.255 31 0
192.168.1.1 192.168.1.255 24 0