Re: Need help to modify 'character_set_database'

[Rick James]

Quote

The character set and collation for the default database can be determined from the values of the character_set_database and collation_database system variables. The server sets these variables whenever the default database changes. If there is no default database, the variables have the same value as the corresponding server-level system variables, character_set_server and collation_server.

-- http://dev.mysql.com/doc/refman/5.1/en/charset-database.html

That is, you don't. Instead it is a 'readonly' value that comes from elsewhere. Example:

mysql> CREATE DATABASE db_utf8 DEFAULT CHARACTER SET = utf8;
Query OK, 1 row affected (0.07 sec)

mysql> CREATE DATABASE db_latin1 DEFAULT CHARACTER SET = latin1;
Query OK, 1 row affected (0.01 sec)

mysql> USE db_utf8;
Database changed
mysql> SHOW VARIABLES LIKE 'char%';
+--------------------------+-----------------------------------------------+
| Variable_name            | Value                                         |
+--------------------------+-----------------------------------------------+
| character_set_client     | latin1                                        |
| character_set_connection | latin1                                        |
| character_set_database   | utf8                                          |
| character_set_filesystem | binary                                        |
| character_set_results    | latin1                                        |
| character_set_server     | utf8                                          |
| character_set_system     | utf8                                          |
| character_sets_dir       | ... |
+--------------------------+-----------------------------------------------+
8 rows in set (0.00 sec)

mysql> USE db_latin1;
Database changed
mysql> SHOW VARIABLES LIKE 'char%';
+--------------------------+-----------------------------------------------+
| Variable_name            | Value                                         |
+--------------------------+-----------------------------------------------+
| character_set_client     | latin1                                        |
| character_set_connection | latin1                                        |
| character_set_database   | latin1                                        |
| character_set_filesystem | binary                                        |
| character_set_results    | latin1                                        |
| character_set_server     | utf8                                          |
| character_set_system     | utf8                                          |
| character_sets_dir       | ... |
+--------------------------+-----------------------------------------------+
8 rows in set (0.00 sec)

Why do you think you want to set it?