如何从 ASP.Net 核心中的 PostgreSQL 函数获取数据

Question

我是 asp.net 核心的初学者。我的 posgres 中有一个名为“GetDriverStatusReport”的工作函数将 return 一些数据。我想在我的 Asp.Net 核心应用程序中检索这些值。我尝试对此进行研究，但找不到合适的解决方案。有人可以告诉我在 Asp.net Core 中调用存储过程的正确性吗？提前致谢

这是我的函数

CREATE OR REPLACE FUNCTION GetDriverStatusReport(ref refcursor) RETURNS refcursor AS $$
BEGIN
  OPEN ref FOR (WITH union_tbl AS(
SELECT
   DR."DriverId" AS "Driver Id",
   DR."DriverName" As "Driver Name",                
   0 as "RiderIncome",
   0 as "Payable To Rider",
   0 as "Recievable Balance",
   DR."Amount" as "Amount Paid"
FROM "DriverPaymentReferences" as DR            
UNION ALL
SELECT
   DF."DriverId" AS "Driver Id",
   DF."DriverName" As "Driver Name",
   DF."RiderIncome" as "RiderIncome",
   0 as "Payable To Rider",
   0 as "Recievable Balance",
   0 as "Amount Paid"
FROM "DeliveryFinances" as DF 
UNION ALL
SELECT
   TF."DriverId" AS "Driver Id",
   TF."DriverName" As "Driver Name",
   0 as "RiderIncome",
   TF."PayableToRider" as "Payable To Rider",
   TF."RecievableBalance" as "Recievable Balance",
   0 as "Amount Paid"
FROM "TaxiFinances" as TF)
Select 
   "Driver Id", 
   "Driver Name",
   case when 
     ((Sum("Recievable Balance") - SUM("Payable To Rider")) -Sum("RiderIncome")- 
   SUM("Amount Paid")) > 0
   then 'CR'
   else 'DR' end as "Cash/Debit",
   ((Sum("Recievable Balance") - SUM("Payable To Rider")) -Sum("RiderIncome")- 
   SUM("Amount Paid")) AS "Amount"
FROM union_tbl
GROUP BY "Driver Id","Driver Name" );
  RETURN ref;                                                      
END;
$$ LANGUAGE plpgsql;

Answer 1

嗯，你可以这样试试，

假设我有一个名为 SP_GetAllMSManager 的存储过程，就像这样

PG SQL

CREATE OR REPLACE FUNCTION GetWSManager() 
AS $$

BEGIN
      SELECT DISTINCT  WSManager FROM WsEmployee ORDER BY WSManager 
      COMMIT;      
END;
$$ LANGUAGE plpgsql;

C#ASP.NET核心：

NpgsqlConnection conn = new NpgsqlConnection("Server=127.0.0.1;User Id=postgres;Password=pwd;Database=postgres;");

conn.Open();

// Passing PostGre SQL Function Name
NpgsqlCommand command = new NpgsqlCommand("EXE GetEmployeePrintInfo", conn);

// Execute the query and obtain a result set
NpgsqlDataReader reader = command.ExecuteReader();

// Reading from the database rows
List<string> listOfManager = new List<string>();

while (reader.Read())
{
    string WSManager = reader["WSManager"].ToString(); // Remember Type Casting is required here it has to be according to database column data type
    listOfManager.Add(WSManager);
}
reader.Close();

command.Dispose();
conn.Close();

输出：

如果上下文相同：

如果你想使用相同的上下文，那么你可以尝试这种方式：

C#ASP.NET核心：

  var printJobList =  _context.PrinterJobs
                     .FromSql("EXECUTE GetEmployeePrintInfo")
                     .ToList();

注意：这属于_context.PrinterJobs，意思是store procedure只从PrinterJobstable获取数据。所以我可以按照上面的方式做。但是，如果您的存储过程包含来自 join 的其他实体数据，那么第一种方法会很方便。你可以看看official document here

PG SQL:

CREATE OR REPLACE FUNCTION GetEmployeePrintInfo() 
AS $$
BEGIN
       SELECT DISTINCT PrinterId ,PrinterName,PrintedBy,TotalPrint FROM PrintJob 
       COMMIT;     
END;
$$ LANGUAGE plpgsql;

希望对您有所帮助。

如何从 ASP.Net 核心中的 PostgreSQL 函数获取数据

How to get data from PostgreSQL function in ASP.Net core

c#

postgresql

stored-procedures

asp.net-core-webapi