What is the use of MySQL SUBSTRING_INDEX() function?

MySQL SUBSTRING_INDEX() function returns the substring from a given string before the occurrences of a delimiter. The number of occurrences is specified as an argument of it. It would be more understood with the help of syntax of SUBSTRING_INDEX() function as follows −

Syntax

SUBSTRING_INDEX(Str, delim, count)

Here, 

• Str is the string from which it returns the substring.
• Delim is the delimiter which is to be search in string.
• Count is the number of times the delimiter is to be searched.

Example

mysql> Select SUBSTRING_INDEX('My Name is Ram','a',2);
+-----------------------------------------+
| SUBSTRING_INDEX('My Name is Ram','a',2) |
+-----------------------------------------+
| My Name is R                            |
+-----------------------------------------+
1 row in set (0.00 sec)

The above query returns the substring before the occurrence of second ‘a’ because the delimiter was ‘a’ and count was 2.

mysql> Select SUBSTRING_INDEX('My Name is Ram','a',1);
+-----------------------------------------+
| SUBSTRING_INDEX('My Name is Ram','a',1) |
+-----------------------------------------+
| My N                                    |
+-----------------------------------------+
1 row in set (0.00 sec)

The above query returns the substring before the occurrence of first ‘a’ because the delimiter was ‘a’ and count was 1.