U-SQL存储过程Datetime.Tryparse在哪里

3 回答

• 0

  是的，这可以使用内联功能 . This article显示了如何做到这一点 . 这是一个简单的例子：

  @input = SELECT *
       FROM (
          VALUES
          ( (int)1, (string)"1/1/2017" ),
          ( (int)2, (string)"1/2/2017" ),
          ( (int)3, (string)"bad date" )
       ) AS x ( rn, someString );
  
  
  // inline function example
  @output =
      SELECT *
      FROM
      (
          SELECT *,
                 (
                  (Func<string, DateTime?>)
                  (dateString =>  // input_paramater
                      { 
                          DateTime dateValue;
                          return DateTime.TryParse(dateString, out dateValue) ? (DateTime?)dateValue : (DateTime?)null;
                      }
                   )
              ) (someString) AS someDate
          FROM @input
      ) AS x
      WHERE someDate IS NOT NULL;
  
  
  OUTPUT @output TO "/output/output.csv"
  USING Outputters.Csv(quoting:false);
  

  如果要将已创建的程序集用作U-SQL类项目并进行注册，则可以使用 REFERENCE ASSEMBLY 在存储过程中引用它：

  DROP PROCEDURE IF EXISTS dbo.usp_testCleanDate;
  CREATE PROCEDURE dbo.usp_testCleanDate()
  AS
  BEGIN
  
      REFERENCE ASSEMBLY USQLCSharpProject1;
  
      @input = SELECT *
           FROM (
              VALUES
              ( (int)1, (string)"1/1/2017" ),
              ( (int)2, (string)"1/2/2017" ),
              ( (int)3, (string)"bad date" )
           ) AS x ( rn, someString );
  
  
      @output =
          SELECT *,
                 USQLCSharpProject1.Class1.tryParseDate(someString) AS x
          FROM @input;
  
  
      OUTPUT @output
      TO "/output/output.csv"
      USING Outputters.Csv(quoting : false);
  
  END;
  

  回复于 2024-05-09T08:04:50+08:00
• 1

  Using Function dt_TryParse_USQL
  Using above code-behind and calling function. Function consumes a string and attempts to convert the string to a DateTime value using DateTime.TryParse. Using the Code-Behind above.
  
  @employees = 
      SELECT * FROM 
          ( VALUES
          (1, "Noah",   "2/16/2008"),
          (2, "Sophia", "2/16/2008 12:15:12 PM"),
          (3, "Liam",   "16/02/2008 12:15:12"),
          (4, "Amy",    "2017-01-11T16:52:07"),
          (5, "Justin", "")
          ) AS T(EmpID, EmpName, StartDate);
  
  @result = 
      SELECT  
          EmpID,
          EmpName,
          ReferenceGuide_Examples.MyClass.dt_TryParse_USQL(StartDate) AS validated_StartDate
      FROM @employees;
  
  OUTPUT @result
  TO "/Output/ReferenceGuide/DDL/Functions/dt_TryParse_USQL.csv"
  USING Outputters.Csv(outputHeader: true);
  

  https://msdn.microsoft.com/en-us/azure/data-lake-analytics/u-sql/u-sql-functions

  其他信息：Click here

  回复于 2024-05-09T08:04:50+08:00
• 0

  要回答这部分问题：

  对于存储过程，脚本不会向我的自定义C＃代码添加任何程序集引用，或者在调用存储过程时添加它时未使用它 .

  U-SQL函数和过程带有它们自己的静态上下文，并且不从调用上下文继承静态名称上下文 . 这允许独立于被调用的位置理解函数/过程的语义 .

  因此，为了引用汇编代码，您需要在目录中注册程序集，并使用 REFERENCE ASSEMBLY 在过程内显式引用它 . 代码隐藏不应在程序中使用（因为程序存储以备将来使用） .

  回复于 2024-05-09T08:04:50+08:00