Handle Oracle Database Connection in Dapper - asp.net

Question

I am trying to connect to the Oracle Database and trying to execute a query.
So below is my Model Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations.Schema;
using System.ComponentModel.DataAnnotations;
namespace TestAPI.Models
{
public class TestAPIModel
{
[Key]
public int PRIO_CATEGORY_ID { get; set; }
public int LANG_ID { get; set; }
public System.DateTime REC_DATE { get; set; }
public int REC_USER { get; set; }
public Nullable<int> RFCH_ID { get; set; }
public string DESCR { get; set; }
public string COL_DESCR { get; set; }
public string ROW_DESCR { get; set; }
public string ABBR { get; set; }
}
}
DBContext Class is
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity;
namespace TestAPI.Models
{
public class TestAPIContext: DbContext
{
public DbSet<TestAPIModel> details { get; set; }
}
}
Now trying to create the Controller with the Dapper, now the issue is in most of the forums it is trying to connect to SQL Database. I am trying to access Oracle DB and return the result in JSON format .So if I give
using Oracle.ManagedDataAccess.Client;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using Newtonsoft.Json;
using System.Web.Http.Description;
using TestAPI.Models;
using Dapper;
namespace TestAPI.Controllers
{
public class TestAPIModelsController : ApiController
{
// GET: api/TestAPIModels
public IQueryable<TestAPIModel> Getdetails(int id)
{
OracleConnection dbConn = new OracleConnection("DATA SOURCE=AX;PASSWORD=CM;PERSIST SECURITY INFO=True;USER ID=AB");
dbConn.Open();
var strQuery = #"Select PRIO_CATEGORY_ID as PRIO,LANG_ID as LANG, REC_DATE as REC, REC_USER as RECUSER, DESCR,COL_DESCR AS COL,ROW_DESCR as DROW,ABBR from STCD_PRIO_CATEGORY_DESCR where REC_USER = " +id;
retrun dbConn.Query<TestAPIModel>();
dbConn.Close();
}
}
}
It throws an error saying that the dbconn.Query is not in context and I also tried TestAPIContext.Init even that throws error. Can anyone please suggest me how to deal Oracle connection with the Dapper. I am new to ASP.NET and the Creating the services. kind of really stuck, any help is greatly appreciated.

Answer 1

You were not passing the SQL. Also, the explicit close is not needed. You can wrap the code in a using as under the hood SqlConnection.Dispose() calls the SqlConnection.Close().
Perhaps this a typo, but "retrun" should be "return". Connectionstring should be read from the app.config vs. hard coded and I'd also consider making 'id' a parameter.
using (var dbConn = new OracleConnection("DATA SOURCE=AX;PASSWORD=CM;PERSIST SECURITY INFO=True;USER ID=AB"))
{
dbConn.Open();
var strQuery = #"Select PRIO_CATEGORY_ID as PRIO,LANG_ID as LANG, REC_DATE as REC, REC_USER as RECUSER, DESCR,COL_DESCR AS COL,ROW_DESCR as DROW,ABBR from STCD_PRIO_CATEGORY_DESCR where REC_USER = " +id;
return dbConn.Query<TestAPIModel>(strQuery);
}

Answer 2

I could handle this, with the following solution:
1. Install Oracle.ManagedDataAccess.Core Package from nuget.
2. Write ConnectionString as follows:
Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=0.0.0.0)(PORT=1521))(CONNECT_DATA=(SID=sidName))); User Id=*****; Password=******;
PORT=1521 => Default port of Oracle is 1521, you can change it with your Oracle server port
0.0.0.0 => Oracle server IP or name
sidName => SidName of oracle server
3. C# snippet code:
protected IDbConnection GetChargingOracleDbConnection
{
get
{
var oracleConnection = new OracleConnection("OracleConnectionString");
oracleConnection.Open();
return oracleConnection;
}
}
var query = "SELECT Id, Name FROM Service";
using (var dbConnection = GetChargingOracleDbConnection)
{
return dbConnection.Query<MyModel>(query).ToList();
}