If the length of results is greater then the value if the max_allowed_packet system variable then the String-valued functions will return NULL
The first position of a string (for those functions which operate on string), is numbered 1.
Non-integer arguments are rounded to the nearest integer (For functions that take length arguments).
CHAR(N,... [USING charset_name])
CHAR() interprets all argument N as an integer and returns a string. NULL values are skipped.
mysql> SELECT CHAR(77,78);
+-------------+
| CHAR(77,78) |
+-------------+
| MN |
+-------------+
1 row in set (0.00 sec)
mysql> SELECT CHAR(91,78,92,106);
+--------------------+
| CHAR(91,78,92,106) |
+--------------------+
| [N\j |
+--------------------+
1 row in set (0.00 sec)
mysql> SELECT CHAR(97,78,92,106);
+--------------------+
| CHAR(97,78,92,106) |
+--------------------+
| aN\j |
+--------------------+
1 row in set (0.00 sec)
0 Comment(s)