英文:
Querying a messy table in SQL
问题
我可以使用一些帮助来编写一个查询，将我遇到的最奇怪的表之一转化为有用的东西。所以就这样吧... 这是一个SQL表（让我们称其为'阈值'），显示了一个阈值的每周概要。它看起来像这样：
列 1，'产品' = X
列 2，'星期一上午' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
列 3，'星期一下午' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
...
列 15，'星期天下午' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
正如您所看到的，有14列具有阈值值，每半天一个列。在行上，我们有来自（假设）A到Z的产品，每天和每小时都有不同的阈值值。
根据上面的示例，我想要的是：
产品 天 小时 阈值
X 1 0 2
X 1 1 2
X 1 2 2
X 1 3 2
X 1 4 2
X 1 5 2
X 1 6 2
X 1 7 2
X 1 8 2
X 1 9 2
X 1 10 2
X 1 11 2
X 1 12 2
X 1 13 2
X 1 14 2
X 1 15 2
X 1 16 2
X 1 17 2
X 1 18 2
X 1 19 2
X 1 20 2
X 1 21 2
X 1 22 2
X 1 23 2
X 2 0 2
X 2 1 2
X 2 2 2
X 2 3 2
等等...
对于这种类型的转换，我可以使用一些有用的技巧吗？我正在努力！
谢谢您的关注。 :)
<details>
<summary>英文:</summary>
I could use some help writing a query that will turn one of the weirdest tables I've encountered in something useful. So here it goes.. This is an SQL table (let's call it 'THRESHOLDS') that shows a weekly profile of a threshold. It looks like:
Column 1, 'Product' = X
Column 2, 'Monday_AM' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
Column 3, 'Monday_PM' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
...
Column 15, 'Sunday_PM' = 0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2
As you can see, there are 14 columns with threshold values, one column for each half a day. On the rows, we have Products from (let's say) A to Z, all with different threshold values for each day & hour.
What I'd like to have (based on example above) is:
Product Day Hour Threshold
X 1 0 2
X 1 1 2
X 1 2 2
X 1 3 2
X 1 4 2
X 1 5 2
X 1 6 2
X 1 7 2
X 1 8 2
X 1 9 2
X 1 10 2
X 1 11 2
X 1 12 2
X 1 13 2
X 1 14 2
X 1 15 2
X 1 16 2
X 1 17 2
X 1 18 2
X 1 19 2
X 1 20 2
X 1 21 2
X 1 22 2
X 1 23 2
X 2 0 2
X 2 1 2
X 2 2 2
X 2 3 2
etc…
Are there any handy tricks I can use for this type of transformation? I'm struggling!
Thank you for your attention. :)
</details>
# 答案1
**得分**: 2
以下是您要翻译的内容：
您可以使用 `cross apply` 进行反规范化，然后使用 `string_split()` 和一些字符串操作：
select t.product, v.day,
(left(s.value, charindex('-', s.value) - 1) + v.offset) as hour,
stuff(s.value, 1, charindex('-', s.value), '')
from t cross apply
(values (t.monday_am, 1, 0),
(t.monday_pm, 1, 12),
(t.tuesday_am, 2, 0),
. . .
) v(str, day, offset)
string_split(v.str, ';') s
[这里][1] 是一个 db<>fiddle。
<details>
<summary>英文:</summary>
You can unpivot using `cross apply` and then use `string_split()` and some string manipulation:
select t.product, v.day,
(left(s.value, charindex('-', s.value) - 1) + v.offset) as hour,
stuff(s.value, 1, charindex('-', s.value), '')
from t cross apply
(values (t.monday_am, 1, 0),
(t.monday_pm, 1, 12),
(t.tuesday_am, 2, 0),
. . .
) v(str, day, offset)
string_split(v.str, ';') s
[Here][1] is a db<>fiddle.
[1]: https://dbfiddle.uk/?rdbms=sqlserver_2017&fiddle=3f924c4b99bffad80d69ca5032b9962f
</details>
# 答案2
**得分**: 0
这是一个SQL查询代码的部分，涉及表格和列名的处理，代码中包括了对日期和时间的操作。如果您需要针对特定部分进行翻译或有任何其他问题，请提出具体的要求。
<details>
<summary>英文:</summary>
This is nasty, but here it is, only with two days, you get the idea, fiddle [here][1]:
declare @t table([Product] varchar(80), [Day] int,
[Monday_AM] varchar(250),
[Monday_PM] varchar(250),
[Tuesday_AM] varchar(250),
[Tuesday_PM] varchar(250));
insert into @t values('X', 1,
'0-12;1-22;2-32;3-42;4-52;5-62;6-72;7-82;8-92;9-102;10-112;11-122',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2')
insert into @t values('X', 2,
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2')
insert into @t values('X', 3,
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2',
'0-2;1-2;2-2;3-2;4-2;5-2;6-2;7-2;8-2;9-2;10-2;11-2')
;WITH CTEH
AS
(
select
Product,
[Day],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 1) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 1) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 1) - 1)) [Monday_AM_Hour_0],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 2) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 2) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 2) - 1)) [Monday_AM_Hour_1],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 3) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 3) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 3) - 1)) [Monday_AM_Hour_2],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 4) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 4) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 4) - 1)) [Monday_AM_Hour_3],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 5) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 5) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 5) - 1)) [Monday_AM_Hour_4],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 6) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 6) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 6) - 1)) [Monday_AM_Hour_5],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 7) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 7) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 7) - 1)) [Monday_AM_Hour_6],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 8) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 8) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 8) - 1)) [Monday_AM_Hour_7],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 9) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 9) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 9) - 1)) [Monday_AM_Hour_8],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 10) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 10) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 10) - 1)) [Monday_AM_Hour_9],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 11) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 11) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 11) - 1)) [Monday_AM_Hour_10],
Substring(';'+[Monday_AM], dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 12) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_AM], 12) - dbo.[fn_Nth_Pos](';', ';'+[Monday_AM], 12) - 1)) [Monday_AM_Hour_11],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 1) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 1) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 1) - 1)) [Monday_PM_Hour_0],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 2) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 2) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 2) - 1)) [Monday_PM_Hour_1],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 3) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 3) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 3) - 1)) [Monday_PM_Hour_2],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 4) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 4) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 4) - 1)) [Monday_PM_Hour_3],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 5) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 5) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 5) - 1)) [Monday_PM_Hour_4],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 6) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 6) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 6) - 1)) [Monday_PM_Hour_5],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 7) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 7) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 7) - 1)) [Monday_PM_Hour_6],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 8) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 8) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 8) - 1)) [Monday_PM_Hour_7],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 9) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 9) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 9) - 1)) [Monday_PM_Hour_8],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 10) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 10) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 10) - 1)) [Monday_PM_Hour_9],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 11) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 11) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 11) - 1)) [Monday_PM_Hour_10],
Substring(';'+[Monday_PM], dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 12) + 1, (dbo.[fn_Nth_Pos]('-', ';'+[Monday_PM], 12) - dbo.[fn_Nth_Pos](';', ';'+[Monday_PM], 12) - 1)) [Monday_PM_Hour_11]
From @t
), CTET AS
(
SELECT
Product,
[Day],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 1) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 1) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 1) - 1)) [Monday_AM_Threshold_0],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 2) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 2) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 2) - 1)) [Monday_AM_Threshold_1],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 3) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 3) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 3) - 1)) [Monday_AM_Threshold_2],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 4) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 4) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 4) - 1)) [Monday_AM_Threshold_3],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 5) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 5) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 5) - 1)) [Monday_AM_Threshold_4],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 6) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 6) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 6) - 1)) [Monday_AM_Threshold_5],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 7) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 7) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 7) - 1)) [Monday_AM_Threshold_6],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 8) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 8) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 8) - 1)) [Monday_AM_Threshold_7],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 9) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 9) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 9) - 1)) [Monday_AM_Threshold_8],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 10) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 10) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 10) - 1)) [Monday_AM_Threshold_9],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 11) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM], 11) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 11) - 1)) [Monday_AM_Threshold_10],
Substring([Monday_AM], dbo.[fn_Nth_Pos]('-', [Monday_AM], 12) + 1, (dbo.[fn_Nth_Pos](';', [Monday_AM]+';', 12) - dbo.[fn_Nth_Pos]('-', [Monday_AM], 12) - 1)) [Monday_AM_Threshold_11],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 1) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 1) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 1) - 1)) [Monday_PM_Threshold_0],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 2) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 2) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 2) - 1)) [Monday_PM_Threshold_1],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 3) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 3) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 3) - 1)) [Monday_PM_Threshold_2],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 4) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 4) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 4) - 1)) [Monday_PM_Threshold_3],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 5) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 5) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 5) - 1)) [Monday_PM_Threshold_4],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 6) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 6) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 6) - 1)) [Monday_PM_Threshold_5],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 7) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 7) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 7) - 1)) [Monday_PM_Threshold_6],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 8) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 8) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 8) - 1)) [Monday_PM_Threshold_7],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 9) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 9) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 9) - 1)) [Monday_PM_Threshold_8],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 10) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 10) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 10) - 1)) [Monday_PM_Threshold_9],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 11) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM], 11) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 11) - 1)) [Monday_PM_Threshold_10],
Substring([Monday_PM], dbo.[fn_Nth_Pos]('-', [Monday_PM], 12) + 1, (dbo.[fn_Nth_Pos](';', [Monday_PM]+';', 12) - dbo.[fn_Nth_Pos]('-', [Monday_PM], 12) - 1)) [Monday_PM_Threshold_11]
FROM @t
)
SELECT
P.Product,
P.[Day],
--P.col_hour,
CASE WHEN P.col_hour LIKE '%PM%' THEN P.[Hour] + 12 ELSE P.[Hour] END [Hour],
--T.col_threshold,
T.Threshold
FROM
CTEH
UNPIVOT([Hour] for [col_hour] IN (
[Monday_AM_Hour_0],[Monday_AM_Hour_1],[Monday_AM_Hour_2],[Monday_AM_Hour_3],[Monday_AM_Hour_4],[Monday_AM_Hour_5],[Monday_AM_Hour_6],[Monday_AM_Hour_7],[Monday_AM_Hour_8],[Monday_AM_Hour_9],[Monday_AM_Hour_10],[Monday_AM_Hour_11],
[Monday_PM_Hour_0],[Monday_PM_Hour_1],[Monday_PM_Hour_2],[Monday_PM_Hour_3],[Monday_PM_Hour_4],[Monday_PM_Hour_5],[Monday_PM_Hour_6],[Monday_PM_Hour_7],[Monday_PM_Hour_8],[Monday_PM_Hour_9],[Monday_PM_Hour_10],[Monday_PM_Hour_11]
)) P
INNER JOIN
(
SELECT *
FROM
CTET
unpivot([Threshold] FOR [col_threshold] IN (
[Monday_AM_Threshold_0],[Monday_AM_Threshold_1],[Monday_AM_Threshold_2],[Monday_AM_Threshold_3],[Monday_AM_Threshold_4],[Monday_AM_Threshold_5],[Monday_AM_Threshold_6],[Monday_AM_Threshold_7],[Monday_AM_Threshold_8],[Monday_AM_Threshold_9],[Monday_AM_Threshold_10],[Monday_AM_Threshold_11],
[Monday_PM_Threshold_0],[Monday_PM_Threshold_1],[Monday_PM_Threshold_2],[Monday_PM_Threshold_3],[Monday_PM_Threshold_4],[Monday_PM_Threshold_5],[Monday_PM_Threshold_6],[Monday_PM_Threshold_7],[Monday_PM_Threshold_8],[Monday_PM_Threshold_9],[Monday_PM_Threshold_10],[Monday_PM_Threshold_11]
)) T
) T ON P.Product = T.Product and P.[Day] = T.[Day] and REPLACE(P.col_hour, 'Hour', 'Threshold') = T.col_threshold
[1]: https://dbfiddle.uk/?rdbms=sqlserver_2017&fiddle=55add108c905d8689854ebfb59c33052
</details>
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