I'm losing my mind on this issue since yesterday.
I'm trying to convert my MySQL database from utf8 to utf8mb4. To do so, I followed those sites/threads : https://mathiasbynens.be/notes/mysql-utf8mb4#utf8-to-utf8mb4 , Cannot store emoji in database , Change MySQL default character set to UTF-8 in my.cnf? , etc.
My database seems to have a utf8mb4_unicode_ci collation as expected, and all her tables too.
Nevertheless, when I proceed SHOW VARIABLES WHERE Variable_name LIKE 'character\_set\_%' OR Variable_name LIKE 'collation%'; I obtain :
#With a Root access
Variable_name              Value
character_set_client        utf8                #expecting utf8mb4
character_set_connection    utf8                #expecting utf8mb4
character_set_database      utf8mb4             #good
character_set_filesystem    binary              #good
character_set_results       utf8                #expecting utf8mb4
character_set_server        utf8mb4             #good
character_set_system        utf8                #expecting utf8mb4
collation_connection        utf8_general_ci     #expecting utf8mb4_unicode_ci
collation_database          utf8mb4_unicode_ci  #good
collation_server            utf8mb4_unicode_ci  #good
#With a standard user access
Variable_name               Value
character_set_client        utf8                #expecting utf8mb4
character_set_connection    utf8mb4             #good 
character_set_database      utf8mb4             #good
character_set_filesystem    binary              #good
character_set_results       utf8                #expecting utf8mb4
character_set_server        utf8mb4             #good
character_set_system        utf8                #expecting utf8mb4
collation_connection        utf8mb4_unicode_ci  #good
collation_database          utf8mb4_unicode_ci  #good
collation_server            utf8mb4_unicode_ci  #good
I set a /etc/mysql/conf.d/90-my.cnf file like this :
[client]
default-character-set = utf8mb4
[mysql]
default-character-set = utf8mb4
[mysqld]
character-set-client-handshake = FALSE
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
init-connect = 'SET collation_connection = utf8mb4_unicode_ci'
init-connect = 'SET NAMES utf8mb4'
My MySQL version is 5.5.54, all set in a debian 7.
Does anyone have a clue to help me ?
Thx for your help, and sorry for my bad english...
EDIT
Fun fact : when I check variables in the in-line command, I got this :
mysql> show variables like "%character%";
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8mb4                    |
| character_set_connection | utf8mb4                    |
| character_set_database   | utf8mb4                    |
| character_set_filesystem | binary                     |
| character_set_results    | utf8mb4                    |
| character_set_server     | utf8mb4                    |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
While I still have utf8 for character_set_client and character_set_results when I check with phpmyadmin (with a non-superuser access)
 
     
    