substring_index
Name
SUBSTRING_INDEX
description
Syntax
VARCHAR substring_index(VARCHAR content, VARCHAR delimiter, INT field)
Split content to two parts at position where the fields of delimiter stays, return one of them according to below rules:
if field is positive, return the left part;
else if field is negative, return the right part;
if field is zero, return an empty string when content is not null, else will return null.
delimiteris case sensitive and multi-byte safe.delimiterandfieldparameter should be constant.
example
mysql> select substring_index("hello world", " ", 1);
+----------------------------------------+
| substring_index("hello world", " ", 1) |
+----------------------------------------+
| hello |
+----------------------------------------+
mysql> select substring_index("hello world", " ", 2);
+----------------------------------------+
| substring_index("hello world", " ", 2) |
+----------------------------------------+
| hello world |
+----------------------------------------+
mysql> select substring_index("hello world", " ", -1);
+-----------------------------------------+
| substring_index("hello world", " ", -1) |
+-----------------------------------------+
| world |
+-----------------------------------------+
mysql> select substring_index("hello world", " ", -2);
+-----------------------------------------+
| substring_index("hello world", " ", -2) |
+-----------------------------------------+
| hello world |
+-----------------------------------------+
mysql> select substring_index("hello world", " ", -3);
+-----------------------------------------+
| substring_index("hello world", " ", -3) |
+-----------------------------------------+
| hello world |
+-----------------------------------------+
mysql> select substring_index("hello world", " ", 0);
+----------------------------------------+
| substring_index("hello world", " ", 0) |
+----------------------------------------+
| |
+----------------------------------------+keywords
SUBSTRING_INDEX, SUBSTRING