mysql> CREATE TABLE item_category (
    -> category_id INT,
    -> category_name VARCHAR(256)
    -> );
Query OK, 0 rows affected (0.02 sec)

mysql> INSERT INTO item_category VALUES (1, '家具');
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO item_category VALUES (2, '飲料');
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO item_category VALUES (3, '食品');
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM item_category;
+-------------+---------------+
| category_id | category_name |
+-------------+---------------+
|           1 | 家具          |
|           2 | 飲料          |
|           3 | 食品          |
+-------------+---------------+
3 rows in set (0.00 sec)

mysql> CREATE TABLE items (
    -> item_id INT,
    -> name VARCHAR(256),
    -> price INT,
    -> category_id INT
    -> );
Query OK, 0 rows affected (0.02 sec)

mysql> INSERT INTO items VALUES (1, 'ローマのテーブル', 150000, 1);
Query OK, 1 row affected (0.01 sec)

mysql> INSERT INTO items VALUES (2, 'げーたるーど2000 500ml', 370, 2);
Query OK, 1 row affected (0.01 sec)

mysql> INSERT INTO items VALUES (3, '原始肉', 2500, 3);l
Query OK, 1 row affected (0.01 sec)

    -> INSERT INTO items VALUES (4, '魅惑の椅子', 100000, 1);
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'l
INSERT INTO items VALUES (4, '魅惑の椅子', 100000, 1)' at line 1
mysql> INSERT INTO items VALUES (3, '原始肉', 2500, 3);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO items VALUES (4, '魅惑の椅子', 100000, 1);
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM items;
+---------+------------------------+--------+-------------+
| item_id | name                   | price  | category_id |
+---------+------------------------+--------+-------------+
|       1 | ローマのテーブル       | 150000 |           1 |
|       2 | げーたるーど2000 500ml |    370 |           2 |
|       3 | 原始肉                 |   2500 |           3 |
|       3 | 原始肉                 |   2500 |           3 |
|       4 | 魅惑の椅子             | 100000 |           1 |
+---------+------------------------+--------+-------------+
5 rows in set (0.00 sec)

mysql> DELETE FROM items WHERE item_id = 3;
Query OK, 2 rows affected (0.00 sec)

mysql> SELECT * FROM items;
+---------+------------------------+--------+-------------+
| item_id | name                   | price  | category_id |
+---------+------------------------+--------+-------------+
|       1 | ローマのテーブル       | 150000 |           1 |
|       2 | げーたるーど2000 500ml |    370 |           2 |
|       4 | 魅惑の椅子             | 100000 |           1 |
+---------+------------------------+--------+-------------+
3 rows in set (0.00 sec)

mysql> INSERT INTO items VALUES (3, '原始肉', 2500, 3);
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM items;
+---------+------------------------+--------+-------------+
| item_id | name                   | price  | category_id |
+---------+------------------------+--------+-------------+
|       1 | ローマのテーブル       | 150000 |           1 |
|       2 | げーたるーど2000 500ml |    370 |           2 |
|       4 | 魅惑の椅子             | 100000 |           1 |
|       3 | 原始肉                 |   2500 |           3 |
+---------+------------------------+--------+-------------+
4 rows in set (0.00 sec)

mysql> DELETE FROM items WHERE item_id = 4;
Query OK, 1 row affected (0.01 sec)

mysql> INSERT INTO items VALUES (4, '魅惑の椅子', 100000, 1);
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM items;
+---------+------------------------+--------+-------------+
| item_id | name                   | price  | category_id |
+---------+------------------------+--------+-------------+
|       1 | ローマのテーブル       | 150000 |           1 |
|       2 | げーたるーど2000 500ml |    370 |           2 |
|       3 | 原始肉                 |   2500 |           3 |
|       4 | 魅惑の椅子             | 100000 |           1 |
+---------+------------------------+--------+-------------+
4 rows in set (0.00 sec)

mysql> SELECT items.category_id, items.item_id, items.name, items.price, item_category.category_name FROM items INNER JOIN item_category ON items.category_id = item_category.category_id;
+-------------+---------+------------------------+--------+---------------+
| category_id | item_id | name                   | price  | category_name |
+-------------+---------+------------------------+--------+---------------+
|           1 |       1 | ローマのテーブル       | 150000 | 家具          |
|           2 |       2 | げーたるーど2000 500ml |    370 | 飲料          |
|           3 |       3 | 原始肉                 |   2500 | 食品          |
|           1 |       4 | 魅惑の椅子             | 100000 | 家具          |
+-------------+---------+------------------------+--------+---------------+
4 rows in set (0.00 sec)

mysql> SELECT items.category_id, items.item_id, items.name, items.price, item_category.category_name FROM items INNER JOIN item_category ON items.category_id = item_category.category_id ORDER BY price ASC;
+-------------+---------+------------------------+--------+---------------+
| category_id | item_id | name                   | price  | category_name |
+-------------+---------+------------------------+--------+---------------+
|           2 |       2 | げーたるーど2000 500ml |    370 | 飲料          |
|           3 |       3 | 原始肉                 |   2500 | 食品          |
|           1 |       4 | 魅惑の椅子             | 100000 | 家具          |
|           1 |       1 | ローマのテーブル       | 150000 | 家具          |
+-------------+---------+------------------------+--------+---------------+
4 rows in set (0.00 sec)

mysql> SELECT items.category_id, items.item_id, items.name, items.price, item_category.category_name FROM items INNER JOIN item_category ON items.category_id = item_category.category_id AND items.category_id = 1;
+-------------+---------+------------------+--------+---------------+
| category_id | item_id | name             | price  | category_name |
+-------------+---------+------------------+--------+---------------+
|           1 |       1 | ローマのテーブル | 150000 | 家具          |
|           1 |       4 | 魅惑の椅子       | 100000 | 家具          |
+-------------+---------+------------------+--------+---------------+
2 rows in set (0.00 sec)

mysql> SELECT items.category_id, items.item_id, items.name, items.price, item_category.category_name FROM items INNER JOIN item_category ON items.category_id = item_category.category_id AND 1000 <= items.price AND items.price <= 50000;
+-------------+---------+--------+-------+---------------+
| category_id | item_id | name   | price | category_name |
+-------------+---------+--------+-------+---------------+
|           3 |       3 | 原始肉 |  2500 | 食品          |
+-------------+---------+--------+-------+---------------+
1 row in set (0.00 sec)

mysql> SELECT COUNT(*) AS data_count FROM items;
+------------+
| data_count |
+------------+
|          4 |
+------------+
1 row in set (0.00 sec)

mysql> CREATE TABLE items_category AS SELECT items.category_id, items.item_id, items.name, items.price, item_category.category_name FROM items INNER JOIN item_category ON items.category_id = item_category.category_id ORDER BY price ASC;
Query OK, 4 rows affected (0.03 sec)
Records: 4  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM items_category WHERE price = (SELECT MAX(price) FROM items_category);
+-------------+---------+------------------+--------+---------------+
| category_id | item_id | name             | price  | category_name |
+-------------+---------+------------------+--------+---------------+
|           1 |       1 | ローマのテーブル | 150000 | 家具          |
+-------------+---------+------------------+--------+---------------+
1 row in set (0.00 sec)

mysql> SELECT * FROM items_category WHERE name LIKE '%の%';
+-------------+---------+------------------+--------+---------------+
| category_id | item_id | name             | price  | category_name |
+-------------+---------+------------------+--------+---------------+
|           1 |       4 | 魅惑の椅子       | 100000 | 家具          |
|           1 |       1 | ローマのテーブル | 150000 | 家具          |
+-------------+---------+------------------+--------+---------------+
2 rows in set (0.00 sec)