如何处理SQL Server中的envelope []数据

Question

数据收集器将时间序列数据发送到sql server 2008.为了使数据表更简洁，时间序列以envelop []的形式发送。 这是存储在sql server

中的数据

我的工作是在每一行中对READINGS列求和，例如在上表中得到（0,18,22,28，...）之和。如果有任何函数在sql server中展开{envelope：[{0,0]，...}等数据？

Answer 1

借助解析器UDF

Declare @YourTable table (Readings varchar(50))
Insert Into @YourTable values
('{envelope:[{0:0},{1:18},{2:22},{3:28},]}'),
('{envelope:[{0:0},{1:12},{2:17},{3:24},]}')

Select A.*
      ,B.Total 
 From  @YourTable A
 Cross Apply (Select Total = sum(cast(Substring(Key_Value,1,charindex('}',Key_Value)-1) as int)) from  [dbo].[udf-Str-Parse](Readings,':') where ISNUMERIC(left(Key_Value,1))=1 ) B

返回

Readings                                    Total
{envelope:[{0:0},{1:18},{2:22},{3:28},]}    68
{envelope:[{0:0},{1:12},{2:17},{3:24},]}    53

UDF（如果需要）

CREATE FUNCTION [dbo].[udf-Str-Parse] (@String varchar(max),@Delimeter varchar(10))
--Usage: Select * from [dbo].[udf-Str-Parse]('Dog,Cat,House,Car',',')
--       Select * from [dbo].[udf-Str-Parse]('John Cappelletti was here',' ')

Returns @ReturnTable Table (Key_PS int IDENTITY(1,1), Key_Value varchar(max))
As
Begin
   Declare @XML xml;Set @XML = Cast('<x>' + Replace(@String,@Delimeter,'</x><x>')+'</x>' as XML)
   Insert Into @ReturnTable Select ltrim(rtrim(String.value('.', 'varchar(max)'))) FROM @XML.nodes('x') as T(String)
   Return 
End