我试图通过删除所有PHP循环膨胀来缩短我的代码。我有以下表结构：
tdata_weight
-----
INT id (PK)
VARCHAR Name
DOUBLE Weight
TIMESTAMP StartDate
TIMESTAMP EndDate
我想在WEEKOFYEAR()和StartDate之间生成所有可能的EndDate字段，显示当前年份并将Weight除以所有可能{{1}的计数}}的
因此结果表看起来像这样：
WEEKOFYEAR()我当前的解决方案涉及在PHP中循环遍历表，但我想通过SQL查询完成大部分工作来缩短它...如果可能的话。
修改
这是我的数据：
tdata_weight_part
-----
VARCHAR Name
DOUBLE WeightPart
INT Year
INT Week
我想将其处理到此表中：
id: 1
Name: 'Machine1'
Weight: 50000
StartDate: 2015-03-01 00:00:00
EndDate: 2016-04-09 00:00:00
我知道Name: 'Machine1'
WeightPart: 862.07
Year: 2015
Week: 9
Name: 'Machine1'
WeightPart: 862.07
Year: 2015
Week: 10
Name: 'Machine1'
WeightPart: 862.07
Year: 2015
Week: 11
(...)
Name: 'Machine1'
WeightPart: 862.07
Year: 2016
Week: 14
和WEEKOFYEAR()之间存在 58 StartDate的差异。 EndDate从 2015 第9周开始，StartDate在 2016年第14周结束 / strong>即可。 2015年总共 53 周。
答案 0 :(得分：1)
mysql中的每一件事都是可能的 有一种方法可以找到日期之间的差异 喜欢
SELECT TIMESTAMPDIFF(WEEK,'2016-02-01','2016-02-29');
通过使用此查询，您可以获得开始日期和结束日期之间的星期数
SELECT TIMESTAMPDIFF(WEEK,StartDate,EndDate);
修改
set @a = 0;
set @timeDiffence := TIMESTAMPDIFF(WEEK, '2015-03-01 00:00:00', '2016-04-09 00:00:00');
set @start_week_of_year := WEEKOFYEAR('2015-03-01');
set @start_year := YEAR('2015-03-01');
SELECT weeks, years FROM (
select @start_week_of_year AS weeks, @start_year AS years,IF(@start_week_of_year = 52, @start_year := @start_year + 1,'' ),
IF(@start_week_of_year < 52, @start_week_of_year := @start_week_of_year +1, @start_week_of_year := 1),
if(@a < @timeDiffence, @a := @a+1, @a := null) from
(select adddate('1970-01-01',t4.i*10000 + t3.i*1000 + t2.i*100 + t1.i*10 + t0.i) selected_date from
(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t0,
(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t1,
(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t2,
(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t3,
(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t4) v
where selected_date between '2015-03-01' and '2016-04-09' and @a is not null) AS TEMP;
这将为您提供两个日期之间的周和年 输出
+-------+-------+
| weeks | years |
+-------+-------+
| 9 | 2015 |
| 10 | 2015 |
| 11 | 2015 |
| 12 | 2015 |
| 13 | 2015 |
| 14 | 2015 |
| 15 | 2015 |
| 16 | 2015 |
| 17 | 2015 |
| 18 | 2015 |
| 19 | 2015 |
| 20 | 2015 |
| 21 | 2015 |
| 22 | 2015 |
| 23 | 2015 |
| 24 | 2015 |
| 25 | 2015 |
| 26 | 2015 |
| 27 | 2015 |
| 28 | 2015 |
| 29 | 2015 |
| 30 | 2015 |
| 31 | 2015 |
| 32 | 2015 |
| 33 | 2015 |
| 34 | 2015 |
| 35 | 2015 |
| 36 | 2015 |
| 37 | 2015 |
| 38 | 2015 |
| 39 | 2015 |
| 40 | 2015 |
| 41 | 2015 |
| 42 | 2015 |
| 43 | 2015 |
| 44 | 2015 |
| 45 | 2015 |
| 46 | 2015 |
| 47 | 2015 |
| 48 | 2015 |
| 49 | 2015 |
| 50 | 2015 |
| 51 | 2015 |
| 52 | 2015 |
| 1 | 2016 |
| 2 | 2016 |
| 3 | 2016 |
| 4 | 2016 |
| 5 | 2016 |
| 6 | 2016 |
| 7 | 2016 |
| 8 | 2016 |
| 9 | 2016 |
| 10 | 2016 |
| 11 | 2016 |
| 12 | 2016 |
| 13 | 2016 |
| 14 | 2016 |
+-------+-------+
58 rows in set (0.09 sec)