How to use SUBSTRING_INDEX() MySQL

The SUBSTRING_INDEX() function returns a substring of a string before a specified number of delimiter occurs.

mysql> SELECT ip, SUBSTRING_INDEX(ip,’.’,1) AS part1,

SUBSTRING_INDEX(SUBSTRING_INDEX(ip,'.',2),'.',-1) AS part2, 
SUBSTRING_INDEX(SUBSTRING_INDEX(ip,'.',-2),'.',1) AS part3, 
SUBSTRING_INDEX(ip,'.',-1) AS part4  FROM log_file;
+-----------------+-------+-------+-------+-------+
| ip              | part1 | part2 | part3 | part4 |
+-----------------+-------+-------+-------+-------+
| 127.0.0.1       | 127   | 0     | 0     | 1     |
| 192.128.0.15    | 192   | 128   | 0     | 15    |
| 255.255.255.255 | 255   | 255   | 255   | 255   |
+-----------------+-------+-------+-------+-------+
3 rows in set (0.00 sec)