NET_IP_NET_MASK-MaxCompute(MaxCompute)-阿里云帮助中心

The NET_IP_NET_MASK function generates an IPv4 or IPv6 network mask address based on a specified prefix length.

Syntax

BINARY NET_IP_NET_MASK(BIGINT <num_output_bytes>, BIGINT <prefix_length>)

Parameters

num_output_bytes: Required. A BIGINT value that specifies the number of bytes in the network mask. Valid values are 4 for IPv4 and 16 for IPv6.
prefix_length: Required. A BIGINT value that specifies the prefix length of the network mask. The prefix length is the number of bits that are set to 1 in the mask. The value must be in the range of [0, num_output_bytes × 8].

Return value

Returns an IP address of the BINARY type. You can use this function with the NET_IP_TO_STRING function to convert the address to a readable format. The following rules apply:

If num_output_bytes is not 4 for IPv4 or 16 for IPv6, the function reports an error.
Note
If the odps.sql.udf.strict.mode parameter is set to false, the function returns NULL.
If prefix_length is a negative value or is greater than 8 × num_output_bytes, the function reports an error.
Note
If the odps.sql.udf.strict.mode parameter is set to false, the function returns NULL.
If num_output_bytes or prefix_length is NULL, the function returns NULL.

Examples

Example 1: Basic example

-- Returns =FF=FF=FF=00 
SELECT NET_IP_NET_MASK(4, 24);

-- Returns =FF=FF=F0=00
SELECT NET_IP_NET_MASK(4, 20);

-- Returns =FF=FF=FF=FF
SELECT NET_IP_NET_MASK(4, 32);

-- Returns =00=00=00=00=00=00=00=00=00=00=00=00=00=00=00=00
SELECT NET_IP_NET_MASK(16, 0);

-- Returns =80=00=00=00=00=00=00=00=00=00=00=00=00=00=00=00
SELECT NET_IP_NET_MASK(16, 1);

 -- Returns =FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF=FF
SELECT NET_IP_NET_MASK(16, 128);

-- Returns NULL
SELECT NET_IP_NET_MASK(NULL, 128);

-- Returns NULL
SELECT NET_IP_NET_MASK(4, NULL);

Example 2: Use with the NET_IP_TO_STRING function

You can use this function with the NET_IP_TO_STRING function to convert an IP address of the BINARY type to a readable format.

-- Returns 255.255.255.0
SELECT NET_IP_TO_STRING(NET_IP_NET_MASK(4, 24));

-- Returns ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
SELECT NET_IP_TO_STRING(NET_IP_NET_MASK(16, 128));

-- Returns ffff:ffff:ffff:ffff::
SELECT NET_IP_TO_STRING(NET_IP_NET_MASK(16, 64));

Related functions

NET_IP_NET_MASK is a network function. For more information about network functions, see Network functions.