gistfile1.txt

* latin1のカラムにlatin1の文字

```
mysql57> SET NAMES latin1;
Query OK, 0 rows affected (0.00 sec)

mysql57> INSERT INTO t2 VALUES ('a'), ('あ');
Query OK, 2 rows affected (0.01 sec)
Records: 2  Duplicates: 0  Warnings: 0
```

* latin1で接続すれば読める。

```
mysql57> SELECT val, HEX(val) FROM t2;
+------+----------+
| val  | HEX(val) |
+------+----------+
| a    | 61       |
| あ   | E38182   |
+------+----------+
2 rows in set (0.00 sec)
```

* utf8mb4で読もうとすると化ける

```
mysql57> SET NAMES utf8mb4;
Query OK, 0 rows affected (0.00 sec)

mysql57> SELECT * FROM t2;
+---------+
| val     |
+---------+
| a       |
| a??     |
+---------+
2 rows in set (0.00 sec)
```

* utf8mb4に無理矢理変換するけど、utf8mb4で読もうとすると化けたまま。

```
mysql57> ALTER TABLE t2 CONVERT TO CHARACTER SET utf8mb4;
Query OK, 2 rows affected (0.04 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql57> SELECT val, HEX(val) FROM t2;
+---------+----------------+
| val     | HEX(val)       |
+---------+----------------+
| a       | 61             |
| a??     | C3A3C281E2809A |
+---------+----------------+
2 rows in set (0.00 sec)
```

* latin1で読もうとすると読める不思議。

```
mysql57> SET NAMES latin1;
Query OK, 0 rows affected (0.00 sec)

mysql57> SELECT val, HEX(val) FROM t2;
+------+----------------+
| val  | HEX(val)       |
+------+----------------+
| a    | 61             |
| あ   | C3A3C281E2809A |
+------+----------------+
2 rows in set (0.00 sec)
```

* character_set_databaseの設定も影響してるかも(´・ω・`)