How to perform Linq`s group by and sum operation on List<Dictionary<string, object>>

Question

I have the following code. For every item in objViewForecastTrendYear2 , I'm creating creating DicGridRow dictionary object. I add some properties dynamically along with some static properties in DicGridRow dictionary. At the end I am adding that item in List of Dictionary EntireViewModel . Once I come out of outer loop ,i have List<Dictionary> EntireViewModel .

This list contains some record and i want to apply group by and sum using linq on this EntireViewModel , but I don't know how to do that. Here objViewForecastTrendYear2 is list object which contain all static properties.

Overall scenario is EntireViewModel =( A(static properties)+B(Dynamic properties)) for every item in objViewForecastTrendYear2 .

I want to apply group by on all ID field like UOM_ID and remaining fields in sum operation of Linq on EntireViewModel . My EntireViewModel look like ->

List<Dictionary<string, object>> EntireViewModel = new List<Dictionary<string, object>>();
foreach (var A in objViewForecastTrendYear2)
{
    DynamicColName = new string[NoOfHistoryColumn];
    int HistoryCol = RightHistoryColumn;
    Dictionary<string, object> DicGridRow = new Dictionary<string, object>();
    DicGridRow.Add("COMPANY_ID", A.COMPANY_ID);
    DicGridRow.Add("CUSTOMER_ID", A.CUSTOMER_ID);
    DicGridRow.Add("FINAL_FORECAST", A.FINAL_FORECAST);
    DicGridRow.Add("FINANCIAL_YEAR", A.FINANCIAL_YEAR);
    DicGridRow.Add("FORECAST_MONTH", A.FORECAST_MONTH);
    DicGridRow.Add("FORECAST_PARAMETERS_ID", A.FORECAST_PARAMETERS_ID);
    DicGridRow.Add("MARKET_PLANNER", A.MARKET_PLANNER);
    DicGridRow.Add("PROD_GRADE_ID", A.PROD_GRADE_ID);
    DicGridRow.Add("PROD_ID", A.PROD_ID);
   // DicGridRow.Add("SALES_LAST_YEAR", A.SALES_LAST_YEAR);
    DicGridRow.Add("STATISTICAL_FORECAST", A.STATISTICAL_FORECAST);
    DicGridRow.Add("STOCK_POINT_ID", A.STOCK_POINT_ID);
    DicGridRow.Add("TREND_ID", A.TREND_ID);
    DicGridRow.Add("UOM_ID", A.UOM_ID);
    DicGridRow.Add("VERSION_NO", A.VERSION_NO);
    DicGridRow.Add("CUSTOMER_FORECAST",A.CUSTOMER_FORECAST);

   // Dynamic columns goes as follows
    for (int i = 0; i < NoOfHistoryColumn; i++)
    {
        string strColumnName = Convert.ToString(HistoryCol--);
        DynamicColName[i] = strColumnName;
        //Dictionary<string, object> DicGridRow = new Dictionary<string, object>();
        DicGridRow.Add(strColumnName, A.SALES_LAST_YEAR);
    }

    EntireViewModel.Add(DicGridRow);
}

As you can see my List is of dictionary<string, object> object Now the grouping of List has to be done based upon 2 or more keys of dictionary as we do in SQL databases (ex. PL-SQL).

Answer 1

Here I am able to get required data from List<Dictionary> EntireViewModel . But only static data...Anyone can tell how to add dynamic column in sum operation of linq which is available in EntireViewModel

var DynamicQuery = EntireViewModel
      .GroupBy(d =>
           new{
            FINANCIAL_YEAR= d["FINANCIAL_YEAR"],
             CUSTOMER_ID=d["CUSTOMER_ID"],
             PROD_GRADE_ID = d["PROD_GRADE_ID"],
             PROD_ID = d["PROD_ID"],
              UOM_ID = d["UOM_ID"]
              })
             .Select(x => new
               {
           FINANCIAL_YEAR = x.Key.FINANCIAL_YEAR,
          CUSTOMER_ID = x.Key.CUSTOMER_ID,
          PROD_GRADE_ID = x.Key.PROD_GRADE_ID,
           PROD_ID = x.Key.PROD_ID,
          UOM_ID = x.Key.UOM_ID,
       STATISTICAL_FORECAST = x.Sum(r => Convert.ToDecimal(r["STATISTICAL_FORECAST"])),
            CUSTOMER_FORECAST = x.Sum(r => Convert.ToDecimal(r["CUSTOMER_FORECAST"])),
            MARKET_PLANNER = x.Sum(r => Convert.ToDecimal(r["MARKET_PLANNER"])),
            FINAL_FORECAST = x.Sum(r => Convert.ToDecimal(r["FINAL_FORECAST"]))
           // For Dynamic Column ?????
             }
         );