Re: In fully utf8 unicode MySQL the collation connection makes trouble

[Rick James]

character set settings are important, too:

mysql> show global variables like '%char%';
+--------------------------+-----------------------------------------------+
| Variable_name            | Value                                         |
+--------------------------+-----------------------------------------------+
| character_set_client     | utf8                                          |
| character_set_connection | utf8                                          |
| character_set_database   | utf8                                          |
| character_set_filesystem | binary                                        |
| character_set_results    | utf8                                          |
| character_set_server     | utf8                                          |
| character_set_system     | utf8                                          |
| character_sets_dir       | ... |
+--------------------------+-----------------------------------------------+

Recommend you always explicitly set the collation when create a database or table. MySQL tends to default to 'utf8_general_ci' instead of the "better" (though slower) 'utf8_unicode_ci'.