PolarDB:.NET

Entity Framework

Entity Framework adalah framework object-relational mapping (ORM) populer untuk platform .NET. Saat Anda mengembangkan aplikasi back-end dalam C#, Entity Framework dan Language-Integrated Query (LINQ) dapat mempercepat proses pengembangan secara signifikan.

Driver PolarDB .NET menyediakan file DLL yang mendukung Entity Framework 5 (EF5) dan Entity Framework 6 (EF6).

Untuk informasi selengkapnya tentang Entity Framework, kunjungi situs resmi Entity Framework.

Instal driver .NET

1. Unduh driver .NET.

2. Ekstrak paket driver .NET.

   unzip polardb_oracle_.net.zip

3. Impor driver ke proyek Visual Studio Anda.

   1. Di antarmuka Visual Studio, klik kanan proyek Anda dan pilih Add Reference.

   2. Di kotak dialog Reference Manager, klik Browse.

      Gunakan tombol Browse... untuk memilih file yang akan direferensikan.

   3. Di kotak dialog Select the files to reference, pilih versi driver yang sesuai dan klik Add.

      Sebagai contoh, jika Anda menggunakan .NET Framework 4.5 (folder net45), Anda harus mereferensikan empat file DLL: PolarDB.PolarDBClient.dll, System.Runtime.CompilerServices.Unsafe.dll, System.Threading.Tasks.Extensions.dll, dan System.ValueTuple.dll.

   4. Klik OK.

Contoh

Ikuti langkah-langkah berikut untuk menjalankan proyek contoh.

1. Hubungkan ke kluster database. Untuk informasi selengkapnya, lihat Connect to a database cluster.

2. Jalankan perintah berikut untuk membuat database bernama sampledb.

   CREATE DATABASE sampledb;

3. Impor tabel, data, dan fungsi yang diperlukan untuk contoh ke dalam database sampledb.

   \i ${your path}/PolarDBSample.sql

4. Setelah data diimpor, Anda dapat mulai menulis kode C# Anda.

   Berikut ini contoh cara melakukan kueri, pembaruan, dan pemanggilan prosedur tersimpan.

   using System;
   using System.Data;
   using PolarDB.PolarDBClient;
   /*
    * Kelas ini menyediakan cara sederhana untuk melakukan operasi DML di PolarDB
    *
    * @revision 1.0
    */
   namespace PolarDBClientTest
   {
       class SAMPLE_TEST
       {
           static void Main(string[] args)
           {
               PolarDBConnection conn = new PolarDBConnection("Server=localhost;Port=5432;User Id=polaruser;Password=password;Database=sampledb");
               try
               {
                   conn.Open();
                   //Pernyataan select sederhana menggunakan objek PolarDBCommand
                   PolarDBCommand PolarDBSeletCommand = new PolarDBCommand("SELECT EMPNO,ENAME,JOB,MGR,HIREDATE FROM EMP",conn);
                   PolarDBDataReader SelectResult =  PolarDBSeletCommand.ExecuteReader();
                   while (SelectResult.Read()) 
                   {
                       Console.WriteLine("Emp No" + " " + SelectResult.GetInt32(0));
                       Console.WriteLine("Emp Name" + " " + SelectResult.GetString(1));
                       if (SelectResult.IsDBNull(2) == false)
                           Console.WriteLine("Job" + " " + SelectResult.GetString(2));
                       else
                           Console.WriteLine("Job" + " null ");
                       if (SelectResult.IsDBNull(3) == false)
                           Console.WriteLine("Mgr" + " " + SelectResult.GetInt32(3));
                       else
                           Console.WriteLine("Mgr" + "null");
                       if (SelectResult.IsDBNull(4) == false)
                           Console.WriteLine("Hire Date" + " " + SelectResult.GetDateTime(4));
                       else
                           Console.WriteLine("Hire Date" + " null");
                       Console.WriteLine("---------------------------------");
                   }
                   //Pernyataan insert menggunakan objek PolarDBCommand
                   SelectResult.Close();
                   PolarDBCommand PolarDBInsertCommand = new PolarDBCommand("INSERT INTO EMP(EMPNO,ENAME) VALUES((SELECT COUNT(EMPNO) FROM EMP),'JACKSON')",conn);
                   PolarDBInsertCommand.ExecuteScalar();
                   Console.WriteLine("Record inserted");
                   //Update menggunakan objek PolarDBCommand
                   PolarDBCommand  PolarDBUpdateCommand = new PolarDBCommand("UPDATE EMP SET ENAME ='DOTNET' WHERE EMPNO < 100",conn);
                   PolarDBUpdateCommand.ExecuteNonQuery();
                   Console.WriteLine("Record has been updated");
                   PolarDBCommand PolarDBDeletCommand = new PolarDBCommand("DELETE FROM EMP WHERE EMPNO < 100",conn);
                   PolarDBDeletCommand.CommandType= CommandType.Text;
                   PolarDBDeletCommand.ExecuteScalar();
                   Console.WriteLine("Record deleted");
                   //contoh pemanggilan prosedur
                   try
                   {
                       PolarDBCommand callable_command = new PolarDBCommand("emp_query(:p_deptno,:p_empno,:p_ename,:p_job,:p_hiredate,:p_sal)", conn);
                       callable_command.CommandType = CommandType.StoredProcedure;
                       callable_command.Parameters.Add(new PolarDBParameter("p_deptno",PolarDBTypes.PolarDBDbType.Numeric,10,"p_deptno",ParameterDirection.Input,false ,2,2,System.Data.DataRowVersion.Current,20));
                       callable_command.Parameters.Add(new PolarDBParameter("p_empno", PolarDBTypes.PolarDBDbType.Numeric,10,"p_empno",ParameterDirection.InputOutput,false ,2,2,System.Data.DataRowVersion.Current,7369));
                       callable_command.Parameters.Add(new PolarDBParameter("p_ename", PolarDBTypes.PolarDBDbType.Varchar,10,"p_ename",ParameterDirection.InputOutput,false ,2,2,System.Data.DataRowVersion.Current,"SMITH"));
                       callable_command.Parameters.Add(new PolarDBParameter("p_job", PolarDBTypes.PolarDBDbType.Varchar,10,"p_job",ParameterDirection.Output,false ,2,2,System.Data.DataRowVersion.Current,null));
                       callable_command.Parameters.Add(new PolarDBParameter("p_hiredate", PolarDBTypes.PolarDBDbType.Date,200,"p_hiredate",ParameterDirection.Output,false ,2,2,System.Data.DataRowVersion.Current,null));
                       callable_command.Parameters.Add(new PolarDBParameter("p_sal", PolarDBTypes.PolarDBDbType.Numeric,200,"p_sal",ParameterDirection.Output,false ,2,2,System.Data.DataRowVersion.Current,null));
                       callable_command.Prepare();
                       callable_command.Parameters[0].Value = 20;
                       callable_command.Parameters[1].Value = 7369;
                       PolarDBDataReader result = callable_command.ExecuteReader();
                       int fc = result.FieldCount;
                       for(int i=0;i<fc;i++)
                           Console.WriteLine("RESULT["+i+"]="+ Convert.ToString(callable_command.Parameters[i].Value));
                       result.Close();
                   }
                   // Jika Anda menggunakan driver .NET 2.0, Anda mungkin perlu memodifikasi bagian ini.
                   catch(PolarDBException exp)
                   {
                       if(exp.ErrorCode.Equals("01403"))
                           Console.WriteLine("No data found");
                       else if(exp.ErrorCode.Equals("01422"))
                           Console.WriteLine("More than one row was returned by the query");
                       else
                           Console.WriteLine("There was an error calling the procedure. \nRoot Cause:\n");
                       Console.WriteLine(exp.Message.ToString());
                   }
                   //Pernyataan prepared
                   string updateQuery  = "update emp set ename = :Name where empno = :ID";
                   PolarDBCommand Prepared_command = new PolarDBCommand(updateQuery, conn);
                   Prepared_command.CommandType = CommandType.Text;
                   Prepared_command.Parameters.Add(new PolarDBParameter("ID", PolarDBTypes.PolarDBDbType.Integer));
                   Prepared_command.Parameters.Add(new PolarDBParameter("Name", PolarDBTypes.PolarDBDbType.Text));
                   Prepared_command.Prepare();
                   Prepared_command.Parameters[0].Value = 7369;
                   Prepared_command.Parameters[1].Value = "Mark";
                   Prepared_command.ExecuteNonQuery();
                   Console.WriteLine("Record Updated...");
               }
               catch(PolarDBException exp)
               {
                   Console.WriteLine(exp.ToString() );
               }
               finally
               {
                   conn.Close();
               }
           }
       }
   }

Parameter string koneksi

Saat aplikasi Anda terhubung ke database, aplikasi tersebut harus menyediakan string koneksi yang berisi parameter seperti host, username, dan password.

Format string koneksi adalah keyword1=value; keyword2=value;. Kata kunci tidak peka huruf besar/kecil. Apit nilai yang mengandung karakter khusus, seperti titik koma, dengan tanda kutip ganda ("").

Driver ini mendukung parameter string koneksi berikut.