檢視MySQL變數命令：

show variables;

會出現很多的變數，比如連線超時時間、寫入超時時間、MySQL版本等等

檢視資料庫編碼命令：

show 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       |        |
+--------------------------+--------+
8 rows in set (0.00 sec)

可以展示資料庫相關編碼資訊