SQL - 集合(UNION演算子)

開発環境

• OS: OS X Lion - Apple
• データベース言語: SQL
• リレーショナルデータベース: MySQL

『初めてのSQL』(Alan Beaulieu 著、株式会社クイープ 翻訳、オライリー・ジャパン、2006年、ISBN4-87311-281-8) の6章(集合),　6.5(練習問題)6-2.を解いてみる。

6-2.

入出力結果(Terminal)

$ mysql -u lrngsql -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.5.18 MySQL Community Server (GPL)

Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use bank;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+----------------+
| Tables_in_bank |
+----------------+
| account        |
| branch         |
| business       |
| customer       |
| department     |
| employee       |
| favorite_food  |
| individual     |
| officer        |
| person         |
| product        |
| product_type   |
| tmp            |
| transaction    |
+----------------+
14 rows in set (0.00 sec)

mysql> desc business;
+-------------+------------------+------+-----+---------+-------+
| Field       | Type             | Null | Key | Default | Extra |
+-------------+------------------+------+-----+---------+-------+
| cust_id     | int(10) unsigned | NO   | PRI | NULL    |       |
| name        | varchar(40)      | NO   |     | NULL    |       |
| state_id    | varchar(10)      | NO   |     | NULL    |       |
| incorp_date | date             | YES  |     | NULL    |       |
+-------------+------------------+------+-----+---------+-------+
4 rows in set (0.12 sec)

mysql> desc customer;
+--------------+------------------+------+-----+---------+----------------+
| Field        | Type             | Null | Key | Default | Extra          |
+--------------+------------------+------+-----+---------+----------------+
| cust_id      | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| fed_id       | varchar(12)      | NO   |     | NULL    |                |
| cust_type_cd | enum('I','B')    | NO   |     | NULL    |                |
| address      | varchar(30)      | YES  |     | NULL    |                |
| city         | varchar(20)      | YES  |     | NULL    |                |
| state        | varchar(20)      | YES  |     | NULL    |                |
| postal_code  | varchar(10)      | YES  |     | NULL    |                |
+--------------+------------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)

mysql> desc individual;
+------------+------------------+------+-----+---------+-------+
| Field      | Type             | Null | Key | Default | Extra |
+------------+------------------+------+-----+---------+-------+
| cust_id    | int(10) unsigned | NO   | PRI | NULL    |       |
| fname      | varchar(30)      | NO   |     | NULL    |       |
| lname      | varchar(30)      | NO   |     | NULL    |       |
| birth_date | date             | YES  |     | NULL    |       |
+------------+------------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

mysql> desc employee;
+--------------------+----------------------+------+-----+---------+----------------+
| Field              | Type                 | Null | Key | Default | Extra          |
+--------------------+----------------------+------+-----+---------+----------------+
| emp_id             | smallint(5) unsigned | NO   | PRI | NULL    | auto_increment |
| fname              | varchar(20)          | NO   |     | NULL    |                |
| lname              | varchar(20)          | NO   |     | NULL    |                |
| start_date         | date                 | NO   |     | NULL    |                |
| end_date           | date                 | YES  |     | NULL    |                |
| superior_emp_id    | smallint(5) unsigned | YES  | MUL | NULL    |                |
| dept_id            | smallint(5) unsigned | YES  | MUL | NULL    |                |
| title              | varchar(20)          | YES  |     | NULL    |                |
| assigned_branch_id | smallint(5) unsigned | YES  | MUL | NULL    |                |
+--------------------+----------------------+------+-----+---------+----------------+
9 rows in set (0.00 sec)

mysql> select fname,lanme
    -> from individual
    -> union
    -> select fname,lname
    -> from emloyee;
ERROR 1146 (42S02): Table 'bank.emloyee' doesn't exist
mysql> select fname,lanme from individual union select fname,lname from employee;
ERROR 1054 (42S22): Unknown column 'lanme' in 'field list'
mysql> select fname,lname from individual union select fname,lname from employee;
+----------+-----------+
| fname    | lname     |
+----------+-----------+
| James    | Hadley    |
| Susan    | Tingley   |
| Frank    | Tucker    |
| John     | Hayward   |
| Charles  | Frasier   |
| John     | Spencer   |
| Margaret | Young     |
| Louis    | Blake     |
| Richard  | Farley    |
| Michael  | Smith     |
| Susan    | Barker    |
| Robert   | Tyler     |
| Susan    | Hawthorne |
| John     | Gooding   |
| Helen    | Fleming   |
| Chris    | Tucker    |
| Sarah    | Parker    |
| Jane     | Grossman  |
| Paula    | Roberts   |
| Thomas   | Ziegler   |
| Samantha | Jameson   |
| John     | Blake     |
| Cindy    | Mason     |
| Frank    | Portman   |
| Theresa  | Markham   |
| Beth     | Fowler    |
| Rick     | Tulman    |
+----------+-----------+
27 rows in set (0.02 sec)

mysql> quit
Bye
$