За да съхраните нормалните работни часове, ще трябва да съхраните редица записи, съдържащи:
- Пазарувайте – INTEGER
- Ден от седмицата – INTEGER (0-6)
- OpenTime – TIME
- CloseTime – TIME
Предполагам например, че всеки магазин има намалено работно време по време на национални празници или има спиране на завода, така че ще трябва също да съхранявате някои записи за отмяна:
- Пазарувайте – INTEGER
- OverrideStartDate – DATE
- OverrideEndDate – DATE
- Ден от седмицата – INTEGER (0-6)
- AltOpenTime – TIME
- AltCloseTime – TIME
- Затворено – INTEGER (0, 1)
Намирането на отворени магазини е тривиално, но също така трябва да проверите дали има работно време:
SELECT Shop
FROM OverrideHours
WHERE OverrideStartDate <= NOW()
AND OverrideEndDate >= NOW()
AND DayOfWeek = WEEKDAY(NOW())
Ако има върнати записи, тези магазини имат алтернативно работно време или са затворени.
Може да има някои хубави SQL-fu, които можете да направите тук, но това ви дава основите.
РЕДАКТИРАНЕ
Не съм тествал това, но това трябва да ви доближи:
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))
РЕДАКТИРАНЕ
Що се отнася до ефективността, тя е ефективна в смисъл, че трябва да направите само едно извикване към MySQL, което често е пречка, ако е в мрежа. Ще трябва да тествате и да видите дали това работи според вашите спецификации. Ако не, може да играете с някои индекси.
РЕДАКТИРАНЕ
Тестване. Не пълно тестване, но някои.
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)
