substring
Description
Syntax:
VARCHAR substring(VARCHAR str, INT pos[, INT len])
If len is not specified, this function will return a substring of str starting from pos. If len is specified, it will return a substring of str of length len starting from pos. pos can be negative, if so, the returned substring will be pos characters at the end of str instead of the beginning. If pos is 0, it will return an empty string.
For all forms of SUBSTRING(), the position of the first character is 1.
Example
mysql> select substring('abc1', 2);
+-----------------------------+
| substring('abc1', 2) |
+-----------------------------+
| bc1 |
+-----------------------------+
mysql> select substring('abc1', -2);
+-----------------------------+
| substring('abc1', -2) |
+-----------------------------+
| c1 |
+-----------------------------+
mysql> select substring('abc1', 0);
+----------------------+
| substring('abc1', 0) |
+----------------------+
| |
+----------------------+
mysql> select substring('abc1', 5);
+-----------------------------+
| substring('abc1', 5) |
+-----------------------------+
| NULL |
+-----------------------------+
mysql> select substring('abc1def', 2, 2);
+-----------------------------+
| substring('abc1def', 2, 2) |
+-----------------------------+
| bc |
+-----------------------------+Keywords
SUBSTRING, STRING