https://blog.csdn.net/weixin_44158741/article/details/110469648
可以参考这个帖子

使用达梦自定义函数实现，自定义函数定义如下：

CREATE OR REPLACE FUNCTION INET_ATON( F_ADDRESS IN VARCHAR2 ) RETURN NUMBER 
AS 
    O_ADDRESS_NUMBER NUMBER;
BEGIN
	SELECT
      TO_NUMBER(REGEXP_REPLACE(F_ADDRESS, '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})', '\1')) * 16777216 +
      TO_NUMBER(REGEXP_REPLACE(F_ADDRESS, '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})', '\2')) * 65536 +
      TO_NUMBER(REGEXP_REPLACE(F_ADDRESS, '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})', '\3')) * 256 +
      TO_NUMBER(REGEXP_REPLACE(F_ADDRESS, '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})', '\4')) INTO O_ADDRESS_NUMBER;		
	RETURN O_ADDRESS_NUMBER;	
END INET_ATON;
CREATE OR REPLACE FUNCTION INET_NTOA( F_ADDRESS_NUMBER IN NUMBER ) RETURN VARCHAR2 
AS 
    O_ADDRESS VARCHAR2;
BEGIN
	SELECT TRUNC ( F_ADDRESS_NUMBER / 16777216 ) || '.' || TRUNC ( MOD ( F_ADDRESS_NUMBER, 16777216 ) / 65536 ) || '.' || TRUNC ( MOD ( F_ADDRESS_NUMBER, 65536 ) / 256 ) || '.' || TRUNC ( MOD ( F_ADDRESS_NUMBER, 256 ) ) INTO O_ADDRESS;
	RETURN O_ADDRESS;	
END INET_NTOA;