MariaDB 遺傳了 MySQL 的老問題，utf8 是假的 UTF-8，utf8mb4 才是真的 UTF-8。
參照：
依照我的 CentOS 做出對應修改。
改 /etc/opt/rh/rh-mariadb102/my.cnf.d/mariadb-server.cnf：
[client]
default-character-set = utf8mb4[mysql]
default-character-set = utf8mb4[mysqld]
character-set-server = utf8mb4
character-set-client-handshake = FALSE[mariadb]
character_set_server = utf8mb4
character_set_client = utf8mb4
加上這些設定敘述。
重啟 MariaDB 服務：
> sudo systemctl restart rh-mariadb102-mariadb確認一下狀態：
> sudo systemctl status rh-mariadb102-mariadb進去 MariaDB 看一下現在的編碼：
show variables like 'char%';
show variables like 'collation%';會看到像這樣滿滿的 utf8mb4：
+--------------------------+---------+
| 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 | |
+--------------------------+---------++----------------------+--------------------+
| Variable_name | Value |
+----------------------+--------------------+
| collation_connection | utf8mb4_general_ci |
| collation_database | utf8mb4_general_ci |
| collation_server | utf8mb4_general_ci |
+----------------------+--------------------+
檢視 database、table、column 的編碼
檢視 database 編碼：
SELECT default_character_set_name
FROM information_schema.SCHEMATA
WHERE schema_name = "schemaname";檢視 table 編碼：
SELECT CCSA.character_set_name
FROM information_schema.`TABLES` T, information_schema.`COLLATION_CHARACTER_SET_APPLICABILITY` CCSA
WHERE CCSA.collation_name = T.table_collation
AND T.table_schema = "schemaname"
AND T.table_name = "tablename";檢視 column 編碼：
SELECT character_set_name
FROM information_schema.`COLUMNS`
WHERE table_schema = "schemaname"
AND table_name = "tablename"
AND column_name = "columnname";以上來自 〈How do I see what character set a MySQL database / table / column is?〉。
