存储工作时间并有效查询的最佳方式答案

【问题标题】：Best way to store working hours and query it efficiently存储工作时间并有效查询的最佳方式
【发布时间】：2011-05-26 18:43:08
【问题描述】：

我打算存储商店的工作时间。我想知道工作时间字段的最佳建模是什么，以便我可以非常有效地获取当前打开/关闭的商店列表。

【问题讨论】：

标签： sql mysql database database-design

【解决方案1】：

要存储正常营业时间，您需要存储一些记录，其中包含：

商店 - INTEGER
DayOfWeek - 整数 (0-6)
开放时间 - 时间
关闭时间 - 时间

我假设例如每个商店在国定假日期间减少了工作时间，或者工厂停工，因此您还需要存储一些覆盖记录：

商店 - INTEGER
OverrideStartDate - 日期
覆盖结束日期 - 日期
DayOfWeek - 整数 (0-6)
AltOpenTime - 时间
AltCloseTime - 时间
关闭 - INTEGER (0, 1)

找到营业的商店很简单，但您还需要检查是否有覆盖时间：

SELECT Shop
FROM OverrideHours
WHERE OverrideStartDate <= NOW()
AND OverrideEndDate >= NOW()
AND DayOfWeek = WEEKDAY(NOW())

如果有任何记录返回，这些商店有交替营业时间或关闭。

您可以在这里执行一些不错的 SQL-fu，但这为您提供了基础知识。

编辑

我没有对此进行测试，但这应该会让你接近：

SELECT Normal.Shop
FROM Normal
LEFT JOIN Override
ON Normal.Shop = Override.Shop
AND Normal.DayOfWeek = Override.DayOfWeek
AND NOW() BETWEEN Override.OverrideStartDate AND Override.OverrideEndDate
WHERE Normal.DayOfWeek = WEEKDAY(NOW())
AND ((Override.Shop IS NULL AND TIME(NOW()) BETWEEN Normal.OpenTime AND Normal.CloseTime)
 OR  (Override.Shop IS NOT NULL AND Override.Closed <> 1 AND TIME(NOW()) BETWEEN Override.AltOpenTime AND Override.AltCloseTime))

编辑

至于效率，它是高效的，因为您只需调用一次 MySQL，如果它是跨网络的，这通常是一个瓶颈。您必须测试并查看这是否符合您的规格。如果没有，你可能会玩一些索引。

编辑

测试。未完成测试，但有一些。

mysql> select * from Normal;
+------+-----------+----------+-----------+
| Shop | DayOfWeek | OpenTime | CloseTime |
+------+-----------+----------+-----------+
|    1 |         1 | 09:00:00 | 17:00:00  | 
|    1 |         5 | 09:00:00 | 16:00:00  | 
|    2 |         1 | 09:00:00 | 17:00:00  | 
|    2 |         5 | 09:00:00 | 17:00:00  | 
+------+-----------+----------+-----------+
4 rows in set (0.01 sec)

mysql> select * from Override;
+------+-------------------+-----------------+-----------+-------------+--------------+--------+
| Shop | OverrideStartDate | OverrideEndDate | DayOfWeek | AltOpenTime | AltCloseTime | Closed |
+------+-------------------+-----------------+-----------+-------------+--------------+--------+
|    2 | 2010-12-01        | 2010-12-31      |         1 | 09:00:00    | 18:00:00     |      0 | 
|    2 | 2010-12-01        | 2010-12-31      |         5 | 09:00:00    | 18:00:00     |      0 | 
|    1 | 2010-12-01        | 2010-12-31      |         1 | 09:00:00    | 17:00:00     |      1 | 
+------+-------------------+-----------------+-----------+-------------+--------------+--------+
3 rows in set (0.00 sec)

mysql> SET @whenever = TIMESTAMP('2010-11-23 16:05');
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT WEEKDAY(@whenever);
+--------------------+
| WEEKDAY(@whenever) |
+--------------------+
|                  1 | 
+--------------------+
1 row in set (0.00 sec)

mysql> SELECT Normal.Shop FROM Normal LEFT JOIN Override ON Normal.Shop = Override.Shop AND Normal.DayOfWeek = Override.DayOfWeek AND @whenever BETWEEN Override.OverrideStartDate AND Override.OverrideEndDate WHERE Normal.DayOfWeek = WEEKDAY(@whenever) AND ((Override.Shop IS NULL AND TIME(@whenever) BETWEEN Normal.OpenTime AND Normal.CloseTime)  OR  (Override.Shop IS NOT NULL AND Override.Closed <> 1 AND TIME(@whenever) BETWEEN Override.AltOpenTime AND Override.AltCloseTime));
+------+
| Shop |
+------+
|    1 | 
|    2 | 
+------+
2 rows in set (0.00 sec)

mysql> SET @whenever = TIMESTAMP('2010-11-23 17:05');
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT Normal.Shop FROM Normal LEFT JOIN Override ON Normal.Shop = Override.Shop AND Normal.DayOfWeek = Override.DayOfWeek AND @whenever BETWEEN Override.OverrideStartDate AND Override.OverrideEndDate WHERE Normal.DayOfWeek = WEEKDAY(@whenever) AND ((Override.Shop IS NULL AND TIME(@whenever) BETWEEN Normal.OpenTime AND Normal.CloseTime)  OR  (Override.Shop IS NOT NULL AND Override.Closed <> 1 AND TIME(@whenever) BETWEEN Override.AltOpenTime AND Override.AltCloseTime));
Empty set (0.01 sec)

mysql> SET @whenever = TIMESTAMP('2010-12-25 16:05');
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT Normal.Shop FROM Normal LEFT JOIN Override ON Normal.Shop = Override.Shop AND Normal.DayOfWeek = Override.DayOfWeek AND @whenever BETWEEN Override.OverrideStartDate AND Override.OverrideEndDate WHERE Normal.DayOfWeek = WEEKDAY(@whenever) AND ((Override.Shop IS NULL AND TIME(@whenever) BETWEEN Normal.OpenTime AND Normal.CloseTime)  OR  (Override.Shop IS NOT NULL AND Override.Closed <> 1 AND TIME(@whenever) BETWEEN Override.AltOpenTime AND Override.AltCloseTime));
+------+
| Shop |
+------+
|    2 | 
+------+
1 row in set (0.00 sec)

mysql> SET @whenever = TIMESTAMP('2010-11-23 17:05');
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT WEEKDAY(@whenever);
+--------------------+
| WEEKDAY(@whenever) |
+--------------------+
|                  1 | 
+--------------------+
1 row in set (0.00 sec)

mysql> SELECT Normal.Shop FROM Normal LEFT JOIN Override ON Normal.Shop = Override.Shop AND Normal.DayOfWeek = Override.DayOfWeek AND @whenever BETWEEN Override.OverrideStartDate AND Override.OverrideEndDate WHERE Normal.DayOfWeek = WEEKDAY(@whenever) AND ((Override.Shop IS NULL AND TIME(@whenever) BETWEEN Normal.OpenTime AND Normal.CloseTime)  OR  (Override.Shop IS NOT NULL AND Override.Closed <> 1 AND TIME(@whenever) BETWEEN Override.AltOpenTime AND Override.AltCloseTime));
Empty set (0.00 sec)

【讨论】：

很好的答案！快速提问：在Shop、DayOfWeek、OpenTime 和CloseTime 上放置索引是否可取？
@RabidFire，请参阅stackoverflow.com/questions/3049283/… 的答案。如果您正在寻找的主要效率是查询（例如，与插入相反），那么向 WHERE 或 JOIN ON 中使用的任何字段添加索引应该会加快搜索速度。您必须进行测试，看看哪个最有效。
@Antoniossss，您每天可以输入多个条目... 第 1 天 17:00-11:59:59，第 2 天 00:00-3:00，第 2 天 17:00-11 :59:59，第 3 天 00:00-3:00 等...您的代码必须满足每天输入多个时间的要求。或者，根据您的需要，您可能需要开发不同的模型。
@RobertGowland 你能告诉你AltOpenTime 和AltCloseTime 是什么意思吗？ Someone need to know it :)
@Sami 和 @Belle ，“每个商店在国定假日期间减少了工作时间，或者工厂停工”，这就是 Override 表的目的。列名中的“alt”确实代表“alternative”。从查询中可以看出，如果Override 表中有条目，则使用该表中的小时数。

【解决方案2】：

假设每周的所有营业时间都相同。那么下表呢：

shop_id - INTEGER（或商店的任何唯一标识符）
week_day - INTEGER（0=星期一 - 6=星期日）
opens_at - TIME（使用您当地的时区）
closes_at - TIME（使用您当地的时区）

为shop_id标识的店铺制作一张表格，然后插入营业时间，即：

1、0、8:00、17:00
...
1、5、8:00、12:00
2、0、7:30、12:30
2、0、13:30、17:30
2、1、7:30、12:30
2、1、13:30、17:30
...

然后选择：

SELECT shop_id
FROM opening_hours
WHERE WEEKDAY(NOW()) = week_day
AND TIME(NOW()) BETWEEN opens_at AND closes_at

【讨论】：