MySQLでは次のコマンドを実行するとテーブルスキーマ（カラムなどの構造）を確認できる。
SHOW COLUMNS FROM `users`;
実行結果は次のとおり。
SHOW COLUMNS FROM `users`;
+-----------------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------------------+--------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| mail | varchar(255) | NO | | NULL | |
| tmp_mail | varchar(255) | YES | | NULL | |
| nickname | varchar(20) | YES | | NULL | |
| password | varchar(255) | YES | | NULL | |
| activate_hash | mediumtext | YES | | NULL | |
| activate_date | datetime | YES | | NULL | |
| payment | tinyint(4) | NO | | 2 | |
| period | mediumtext | YES | | NULL | |
| webpay_customer_id | mediumtext | YES | | NULL | |
| webpay_recursion_id | mediumtext | YES | | NULL | |
| payjp_customer_id | mediumtext | YES | | NULL | |
| payjp_subscription_id | mediumtext | YES | | NULL | |
| bank | mediumtext | YES | | NULL | |
| branch | mediumtext | YES | | NULL | |
| bank_type | tinyint(4) | YES | | NULL | |
| bank_number | int(11) | YES | | NULL | |
| bank_meigi | mediumtext | YES | | NULL | |
| evernote_token | mediumtext | YES | | NULL | |
| evernote_expires | datetime | YES | | NULL | |
| type | mediumtext | NO | | NULL | |
| created | datetime | NO | | NULL | |
| modified | datetime | NO | | NULL | |
+-----------------------+--------------+------+-----+---------+----------------+