c# - This row has been removed from a table and does not have any data -

this row has been removed table , not have data. beginedit() allow creation of new data in row.

i have method i'm trying delete duplicate rows (using date) , i'm getting above exception code. understand exception means don't understand i'm doing wrong in code cause it. have looked on several times no luck.

            using (oldstockratingstableadapter ratingsadapter = new oldstockratingstableadapter())             using (dataset.oldstockratingsdatatable ratingstable = new dataset.oldstockratingsdatatable())             {                 ratingsadapter.clearbeforefill = true;                 ratingsadapter.adapter.updatebatchsize = 500;                 ratingsadapter.fillbymarketsymbol(ratingstable, market, symbol);                  var masterquery = c in ratingstable                             c.symbol == symbol && c.market == market                             select c;                 list<dataset.oldstockratingsrow> masterrows = masterquery.tolist();                 list<dataset.oldstockratingsrow> masterdistinctrows = masterquery.distinctby(i => i.date).tolist();                  (int = 0; < masterdistinctrows.count; i++)                 {                     var datequery = c in masterrows                                     c.date == masterdistinctrows.elementatordefault(i).date                                     select c;                     list<dataset.oldstockratingsrow> daterow = datequery.tolist(); // getting exception here                      if (daterow.count > 1)                     {                         (int j = 1; j < daterow.count; j++)                         {                             ratingstable.removeoldstockratingsrow(daterow.elementatordefault(j));                             console.writeline("stock rating deleted " + symbol + " in " + market + " market!");                         }                     }                 }                  // update here                 dataset.oldstockratingsdatatable tempratingstable = new dataset.oldstockratingsdatatable();                 tempratingstable = (dataset.oldstockratingsdatatable)ratingstable.getchanges();                  if (tempratingstable != null)                 {                     ratingsadapter.adapter.updatecommand.updatedrowsource = updaterowsource.none;                     ratingsadapter.adapter.deletecommand.updatedrowsource = updaterowsource.none;                     ratingsadapter.adapter.insertcommand.updatedrowsource = updaterowsource.none;                     ratingsadapter.update(tempratingstable);                     tempratingstable.dispose();                     console.writeline("stock rating calculations finished " + symbol + " in " + market + " market!");                 }  } 

i don't know code if trying delete duplicates maby code of use you:

delete duplicate query x ( select *, row_number() over(partition <column>, checksum(<columns validate>) order <column>) rn <table> ) delete x rn > 1 //it validate multiple columns if more given 

note: code not made me, i'll link origional post here. code posted @dean.