Mysql 数据库模式-表示位置

我需要表示一些事件的位置，我正在为此应用程序设计数据库模式。 我有两种展示位置的方法：

方法1: 4个表：

• 国家
• 州
• 城市
• 位置（在位置I中有国家id、州id和城市id的外键）

方法2: 1表：

• 位置和国家、州、城市字段存储为文本（无外国id）

你会推荐哪种方法？第一个选项将有助于消除同一国家（美国、美国、美国等）可能出现的不同名称，并有助于在文本框中提供建议，这可能是强制性的

然而，第二种方法似乎可以让一切变得更加简单，并且应该减少对数据库的查询数量

你认为哪一个更好？你知道这种情况下的最佳实践是什么吗？例如，在一些大型门户网站上，它是如何做到的，这些门户网站还需要诸如位置之类的东西（如foursquare等）。Afaik facebook使用第二种方法，但是。。。我想听听你的意见，以及你为什么选择一种方法而不是另一种方法的原因

谢谢

方法1:

CREATE TABLE `countries` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `states` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `cities` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_state_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  `fk_cities_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

/* This table should not have fk_country_id and fk_state_id since they are already in their respective tables. but for this requirement I will not remove them from the table */

SELECT locations.name AS location, cities.name AS city, states.name AS state, countries.name AS country from locations INNER JOIN cities ON (cities.id = fk_cities_id) INNER JOIN states ON (states.id = locations.fk_state_id) INNER JOIN countries ON (countries.id = locations.fk_country_id);
+-------------------+---------------+----------+---------------+
| location          | cty          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+
1 row in set (0.00 sec)

EXPLAIN:
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
| id | select_type | table     | type   | possible_keys                          | key     | key_len | ref   | rows | Extra |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
|  1 | SIMPLE      | locations | system | fk_country_id,fk_state_id,fk_cities_id | NULL    | NULL    | NULL  | 7174 |       |
|  1 | SIMPLE      | cities    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | states    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | countries | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` varchar(200) NOT NULL default '',
  `fk_state_id` varchar(200) NOT NULL default '',
  `fk_cities_id` varchar(200) NOT NULL default '',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


SELECT location, city, state, country FROM locations;
+-------------------+---------------+----------+---------------+
| location          | city          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+

如果你想要一个好的解决方案，这是一个很好的解决方案。您可以轻松地管理所有表，但在查询位置时必须有3个左/内联接。我假设所有内容都已正确索引，这样您就不会在性能方面遇到真正的问题，因为这些表相对较小（国家/地区和州），而对于城市（如果您只希望特定国家/地区的所有城市）。如果您想要世界上所有的城市，那么这个表将是巨大的，如果您没有正确地索引或加入表，您可能会在某个时候出现性能问题

由于所有内容都在数据库中，如果需要添加、更新或删除记录，则不必更改代码

如果您需要添加、更新或删除任何记录，此解决方案将非常易于维护。如果您需要更新名称（例如城市名称），则所有记录都将立即更新

如果按城市或州查找，查询将更快地运行，那么一个简单的左连接来获取名称就可以了

方法#2:

CREATE TABLE `countries` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `states` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `cities` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_state_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  `fk_cities_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

/* This table should not have fk_country_id and fk_state_id since they are already in their respective tables. but for this requirement I will not remove them from the table */

SELECT locations.name AS location, cities.name AS city, states.name AS state, countries.name AS country from locations INNER JOIN cities ON (cities.id = fk_cities_id) INNER JOIN states ON (states.id = locations.fk_state_id) INNER JOIN countries ON (countries.id = locations.fk_country_id);
+-------------------+---------------+----------+---------------+
| location          | cty          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+
1 row in set (0.00 sec)

EXPLAIN:
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
| id | select_type | table     | type   | possible_keys                          | key     | key_len | ref   | rows | Extra |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
|  1 | SIMPLE      | locations | system | fk_country_id,fk_state_id,fk_cities_id | NULL    | NULL    | NULL  | 7174 |       |
|  1 | SIMPLE      | cities    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | states    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | countries | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` varchar(200) NOT NULL default '',
  `fk_state_id` varchar(200) NOT NULL default '',
  `fk_cities_id` varchar(200) NOT NULL default '',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


SELECT location, city, state, country FROM locations;
+-------------------+---------------+----------+---------------+
| location          | city          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+

我个人不建议这样做，因为对于可维护性来说，这不是最好的解决方案。如果有一天您需要检索基于某个城市的数据，如果您没有正确索引，您的查询执行起来可能会很慢。如果索引国家、州、城市，则查找速度会更快（但比第一种方法慢，因为索引时varchar比int慢）。此外，您还会增加名称错误的风险，例如：纽约VS纽约VS纽约VS纽约Yrok

此外，如果需要更新城市名称，则必须检索具有该名称的所有记录，然后更新所有这些记录。这可能需要很长时间

例如：更新位置集city='newyork'，其中city='newyork'； *注意：如果您有拼写错误，您必须验证所有记录，以确保更新所有记录

这是一个基于您的需求（使用MYSQL）的框架，用于方法1:

CREATE TABLE `countries` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `states` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `cities` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_state_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  `fk_cities_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

/* This table should not have fk_country_id and fk_state_id since they are already in their respective tables. but for this requirement I will not remove them from the table */

SELECT locations.name AS location, cities.name AS city, states.name AS state, countries.name AS country from locations INNER JOIN cities ON (cities.id = fk_cities_id) INNER JOIN states ON (states.id = locations.fk_state_id) INNER JOIN countries ON (countries.id = locations.fk_country_id);
+-------------------+---------------+----------+---------------+
| location          | cty          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+
1 row in set (0.00 sec)

EXPLAIN:
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
| id | select_type | table     | type   | possible_keys                          | key     | key_len | ref   | rows | Extra |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
|  1 | SIMPLE      | locations | system | fk_country_id,fk_state_id,fk_cities_id | NULL    | NULL    | NULL  | 7174 |       |
|  1 | SIMPLE      | cities    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | states    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | countries | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` varchar(200) NOT NULL default '',
  `fk_state_id` varchar(200) NOT NULL default '',
  `fk_cities_id` varchar(200) NOT NULL default '',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


SELECT location, city, state, country FROM locations;
+-------------------+---------------+----------+---------------+
| location          | city          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+

现在更新：

UPDATE states SET name = 'New York' WHERE ID = 1; //using the primary for update - we only have 1 New York City record in the DB
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

UPDATE locations SET name = 'New York' WHERE name = 'New York City'; // can't use the primary key for update since they are varchars
Query OK, 0 rows affected (1.29 sec)
Rows matched: 151  Changed: 151  Warnings: 0

现在，如果我在我所有的地点寻找那个城市，所有的地点都会说：纽约

对于进近#2:

CREATE TABLE `countries` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `states` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `cities` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_state_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` int(10) NOT NULL DEFAULT '0',
  `fk_state_id` int(10) NOT NULL DEFAULT '0',
  `fk_cities_id` int(10) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

/* This table should not have fk_country_id and fk_state_id since they are already in their respective tables. but for this requirement I will not remove them from the table */

SELECT locations.name AS location, cities.name AS city, states.name AS state, countries.name AS country from locations INNER JOIN cities ON (cities.id = fk_cities_id) INNER JOIN states ON (states.id = locations.fk_state_id) INNER JOIN countries ON (countries.id = locations.fk_country_id);
+-------------------+---------------+----------+---------------+
| location          | cty          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+
1 row in set (0.00 sec)

EXPLAIN:
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
| id | select_type | table     | type   | possible_keys                          | key     | key_len | ref   | rows | Extra |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+
|  1 | SIMPLE      | locations | system | fk_country_id,fk_state_id,fk_cities_id | NULL    | NULL    | NULL  | 7174 |       |
|  1 | SIMPLE      | cities    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | states    | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
|  1 | SIMPLE      | countries | const  | PRIMARY                                | PRIMARY | 4       | const |    1 |       |
+----+-------------+-----------+--------+----------------------------------------+---------+---------+-------+------+-------+

CREATE TABLE `locations` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(200) NOT NULL DEFAULT '',
  `fk_country_id` varchar(200) NOT NULL default '',
  `fk_state_id` varchar(200) NOT NULL default '',
  `fk_cities_id` varchar(200) NOT NULL default '',
  PRIMARY KEY (`id`),
  KEY `fk_country_id` (`fk_country_id`),
  KEY `fk_state_id` (`fk_state_id`),
  KEY `fk_cities_id` (`fk_state_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;


SELECT location, city, state, country FROM locations;
+-------------------+---------------+----------+---------------+
| location          | city          | state    | country       |
+-------------------+---------------+----------+---------------+
| Statue of Liberty | New York City | New York | United States |
+-------------------+---------------+----------+---------------+

现在更新：

UPDATE states SET name = 'New York' WHERE ID = 1; //using the primary for update - we only have 1 New York City record in the DB
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

UPDATE locations SET name = 'New York' WHERE name = 'New York City'; // can't use the primary key for update since they are varchars
Query OK, 0 rows affected (1.29 sec)
Rows matched: 151  Changed: 151  Warnings: 0

现在，如果我在我所有的地点寻找那个城市，并不是所有的地方都会说：纽约

正如你所看到的，它花了1.29秒（是的，它很快），但是所有有“纽约”的记录都被更新了，但可能有一些拼写错误或坏名字等

结论： 仅出于这个原因，我宁愿采用第一种方法

注: 国家和州很少改变。也许您可以在代码中包含这些内容，而不必从数据库中引用它们。这将从查询中保存2个内部连接，并将它们保存在您的代码中，您只需检索国家或州的ID（如果需要创建HTML下拉框，也一样）

---

此外，您可以考虑使用memcached、APC、reddis或任何其他您喜欢的工具来缓存这些国家和州。

使用1，2未规范化，这可能会导致问题。

什么引擎？MySQL？神谕DB9？SqlLite？这有什么重要意义吗？如果是的话，MySQL，但是如果你能指出在Oracle的情况下会有什么不同，那也会很有帮助…是的，我会提供一个实际代码的答案。