Selecting Record to using cursor in stored procedure

Following is an example using cursor to fetch record from table and performing action on each row using while loop, also used try catch in this stored procedure

ALTER PROCEDURE [dbo].[Test_Procedure_By_Khalid]

(

      -- Add the parameters for the stored procedure here

      @TableName nvarchar(255),

      @AreaName varchar(50),

      @SysDate DateTime,

      @ReturnCode INT   OUTPUT

)

AS

     

      DECLARE @GraphID NVARCHAR(50)

      DECLARE @PERIOD INT

      DECLARE @MODELKEY NVARCHAR(50)

      DECLARE @ORIGNALDATE NVARCHAR(50)

      DECLARE @DATE INT

      DECLARE @QTY INT

      DECLARE @TOTALQTY INT

      DECLARE @MODELKEYTYPE INT

      DECLARE @SCREENID NVARCHAR(50)

      DECLARE @RetailModelClassificationName NVARCHAR(50)

      DECLARE @SELECTEDAREA varchar(50)

      DECLARE @INF_Cursor INT

      DECLARE @THEMONTH NVARCHAR(6)

      DECLARE @LASTMONTH NVARCHAR(6)

      DECLARE @LASTYEARMONTH NVARCHAR(6)

      --Cursor Definition

      DECLARE     @Cur_TableParm    CURSOR

     

BEGIN TRY

      ----------------------------

      -- Start Transaction --

      ----------------------------

      BEGIN TRANSACTION

-- Set Cursor to select data from Table CPT_TableParm

      SET @Cur_TableParm = CURSOR FAST_FORWARD FOR

SELECT GraphID,ModelKey,AreaName,ModelClassificationName,ScreenID FROM CPT_TableParm

      WHERE TableName = @TableName

      AND ActFcType = 1

     

      -- Executing Cursor to select data from Table CPT_TableParm

      OPEN  @Cur_TableParm

      FETCH NEXT FROM @Cur_TableParm  INTO

             @GraphID, @MODELKEY,@SELECTEDAREA,

 @RetailModelClassificationName,@SCREENID

     

      -- Looping through cursor result   

      WHILE  @@FETCH_STATUS = 0

        BEGIN

           

Print  @SELECTEDAREA+','+cast(@PERIOD as varchar)+'~'+@MODELKEY+'~'+@ORIGNALDATE+'~'+cast(@DATE as varchar)+'~'+cast(@QTY as varchar)+'~'+

                                          cast(@TOTALQTY as varchar)+'~'+@GraphID+'~''3''~'+@SCREENID

                              SET @ReturnCode = 2

        FETCH NEXT FROM @Cur_TableParm  INTO

                                    @GraphID, @MODELKEY,@SELECTEDAREA,

@RetailModelClassificationName,@SCREENID

       END

      -- Closing @Cur_TableParm to select data from CPT_TableParm

      CLOSE       @Cur_TableParm

      DEALLOCATE  @Cur_TableParm

END TRY

BEGIN CATCH

-- Rollback Transaction --

      ROLLBACK TRANSACTION

      -- Reset Cursor State

      BEGIN

            SET @INF_Cursor = CURSOR_STATUS('global','@Cur_TableParm')

            IF @INF_Cursor = -1

            BEGIN

                  DEALLOCATE  @Cur_TableParm    -- Delete Cursor

            END

            ELSE IF @INF_Cursor <> -3

                  BEGIN

                        CLOSE       @Cur_TableParm    -- Close Cursor

                        DEALLOCATE  @Cur_TableParm    -- Delete Cursor

                  END

            PRINT       ERROR_MESSAGE()

      END

      RETURN 999

END CATCH

Very Simple Data Access Layer for Three Tire Application

Below code is for very simple Data Access Layer that can be use in three tier application, it also includes the Method used in with Transaction

using System;

using System.Configuration;

using System.Data.SqlClient;

using System.Data;

namespace DataAccessLayer

{

    public static class DAcess

    {

        static string constr = "";

        static SqlCommand sqlcom = new SqlCommand();

        static SqlConnection sqlcon = new SqlConnection();

        static SqlDataAdapter sqlda;

        static SqlTransaction SqlTran;

       

        public static void ConnectToDatabase()

        {

            if (sqlcon.State == ConnectionState.Closed)

            {

                constr = ConfigurationManager.ConnectionStrings["ZaaSConString"].ToString();

                sqlcon = new SqlConnection(constr);

                sqlcon.Open();

            }

        }

        public static void DisconnectToDataBase()

        {

            if(sqlcon.State == ConnectionState.Open)

            sqlcon.Close();

        }

        public static DataTable returnDataTable(string Query)

        {

            DataTable dtResult = new DataTable("ResultTable");

            try

            {

                ConnectToDatabase();

                sqlda = new SqlDataAdapter(Query, sqlcon);

                sqlda.Fill(dtResult);

            }

            catch (Exception ex)

            {

            }

            finally

            {

            }

            return dtResult;

        }

        public static DataTable returnDataTableSpecial(string Query)

        {

            DataTable dtResult = new DataTable("ResultTable");

            try

            {

                ConnectToDatabase();

                sqlcom = new SqlCommand(Query, sqlcon, SqlTran);

                sqlda = new SqlDataAdapter(sqlcom);

                sqlda.Fill(dtResult);

            }

            catch (Exception ex)

            {

            }

            finally

            {

            }

            return dtResult;

        }

        public static int ExecuteQuery(string Query)

        {

            int Result = 0;

            try

            {

                ConnectToDatabase();

                sqlcom = new SqlCommand(Query, sqlcon);

                Result = sqlcom.ExecuteNonQuery();

                sqlcon.Close();

            }

            catch (Exception ex)

            {

                sqlcon.Close();

                throw ex;

            }

            finally

            {

                sqlcon.Close();

            }

           

            return Result;

        }

        public static int NewExecuteQuery(string Query)

        {

            int Result = 0;

            sqlcom = new SqlCommand(Query, sqlcon, SqlTran);

            Result = sqlcom.ExecuteNonQuery();

            return Result;

        }

        public static void StartTransaction()

        {

            SqlTran = sqlcon.BeginTransaction(IsolationLevel.ReadUncommitted);

        }

        public static void CommitTransaction()

        {

            SqlTran.Commit();

        }

        public static void RollBackTransaction()

        {

            SqlTran.Rollback();

        }

        public static void CloseTransaction()

        {

            SqlTran.Dispose();

        }

       

       

        public static string returnScalar(string Query)

        {

            string ResultString = "";

            try

            {

                ConnectToDatabase();

                sqlcom = new SqlCommand(Query, sqlcon);

                ResultString = Convert.ToString(sqlcom.ExecuteScalar());

                sqlcon.Close();

            }

            catch (Exception ex)

            {

                sqlcon.Close();

                throw ex;

            }

            finally

            {

                sqlcon.Close();

            }

            return ResultString;

        }

        public static string NewreturnScalar(string Query)

        {

            string ResultString = "";

            sqlcom = new SqlCommand(Query, sqlcon,SqlTran);

            ResultString = Convert.ToString(sqlcom.ExecuteScalar());

            return ResultString;

        }

    }

}