INET_ATON(expr)

MySQL :: MySQL 8.0 Reference Manual :: 12.24 Miscellaneous Functions https://dev.mysql.com/doc/refman/8.0/en/miscellaneous-functions.html#function_inet-aton

 

  • INET_ATON(expr)

    Given the dotted-quad representation of an IPv4 network address as a string, returns an integer that represents the numeric value of the address in network byte order (big endian). INET_ATON() returns NULL if it does not understand its argument.

    mysql> SELECT INET_ATON('10.0.5.9');
            -> 167773449

    For this example, the return value is calculated as 10×2563 + 0×2562 + 5×256 + 9.

    INET_ATON() may or may not return a non-NULL result for short-form IP addresses (such as '127.1' as a representation of '127.0.0.1'). Because of this, INET_ATON()a should not be used for such addresses.

    Note

    To store values generated by INET_ATON(), use an INT UNSIGNED column rather than INT, which is signed. If you use a signed column, values corresponding to IP addresses for which the first octet is greater than 127 cannot be stored correctly. See Section 11.1.7, “Out-of-Range and Overflow Handling”.

  • INET_NTOA(expr)

    Given a numeric IPv4 network address in network byte order, returns the dotted-quad string representation of the address as a string in the connection character set. INET_NTOA() returns NULL if it does not understand its argument.

    mysql> SELECT INET_NTOA(167773449);
            -> '10.0.5.9'

 

 

 

 

 

  • INET_ATON(expr)

    Given the dotted-quad representation of an IPv4 network address as a string, returns an integer that represents the numeric value of the address in network byte order (big endian). INET_ATON() returns NULL if it does not understand its argument.

    mysql> SELECT INET_ATON('10.0.5.9');
            -> 167773449

    For this example, the return value is calculated as 10×2563 + 0×2562 + 5×256 + 9.

    INET_ATON() may or may not return a non-NULL result for short-form IP addresses (such as '127.1' as a representation of '127.0.0.1'). Because of this, INET_ATON()a should not be used for such addresses.

    Note

    To store values generated by INET_ATON(), use an INT UNSIGNED column rather than INT, which is signed. If you use a signed column, values corresponding to IP addresses for which the first octet is greater than 127 cannot be stored correctly. See Section 11.1.7, “Out-of-Range and Overflow Handling”.

  • INET_NTOA(expr)

    Given a numeric IPv4 network address in network byte order, returns the dotted-quad string representation of the address as a string in the connection character set. INET_NTOA() returns NULL if it does not understand its argument.

    mysql> SELECT INET_NTOA(167773449);
            -> '10.0.5.9'
posted @ 2021-10-13 15:59  papering  阅读(139)  评论(0编辑  收藏  举报