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POGetting exception when using linq
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  1. POGetting exception when using linq
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    copied!<p>It's not duplicate of this question(<a href="https://stackoverflow.com/questions/19053489/how-to-do-multiple-joins-when-using-groupby-in-linq">How to do multiple joins when using groupby in linq</a>), situation has changed. </p> <p>I have a picture rating table in my database. For every new rating, a new picture rating table row will be created. I am grouping those ratings by lastweek and pictureid, meaning all the ratings for one single pic in the last week will be accumulated and become one rating.Then i will be able to sort them by their count. Then I am joining two other tables two show user and picture related details. </p> <p>This is my code :</p> <pre><code>public IQueryable&lt;SortedDto&gt; GetOne() { var pastDate = DateTime.Now.Date.AddDays(-1); var combo = from l in db.picturerating where l.iddatetime &gt; pastDate group l by l.idpictures into pgroup let count = pgroup.Count() orderby count descending join p in db.picturedetails on pgroup.FirstOrDefault().idpictures equals p.idpictures into first join u in db.users on pgroup.FirstOrDefault().iduser equals u.iduser into second select new SortedDto { IdPictures = pgroup.FirstOrDefault().idpictures, IdUser = pgroup.FirstOrDefault().iduser, IdDatetime = first.FirstOrDefault().pictime, totalrating = pgroup.Average(l =&gt; (float?)l.rating) ?? 0, sex =second.FirstOrDefault().sex, username =second.FirstOrDefault().username, dob = second.FirstOrDefault().dob }; return combo; } </code></pre> <p>When running this code I get an exception like this :</p> <blockquote> <p>InnerException: {<br> Message: "An error has occurred.",<br> ExceptionMessage: "Unknown column 'Apply1.idpictures' in 'where clause'",<br> ExceptionType: "MySql.Data.MySqlClient.MySqlException" </p> <p>StackTrace:</p> <p>at MySql.Data.MySqlClient.MySqlStream.ReadPacket()<br> at MySql.Data.MySqlClient.NativeDriver.GetResult(Int32&amp; affectedRow, Int64&amp; insertedId) at MySql.Data.MySqlClient.Driver.GetResult(Int32 statementId, Int32&amp; affectedRows, Int64&amp; insertedId) at MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId, Boolean force) at MySql.Data.MySqlClient.MySqlDataReader.NextResult() at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior) at MySql.Data.Entity.EFMySqlCommand.ExecuteDbDataReader(CommandBehavior behavior) at System.Data.Common.DbCommand.ExecuteReader(CommandBehavior behavior) at System.Data.EntityClient.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)</p> </blockquote> <p>So why am I getting this exception? Any thing wrong with my linq query?</p>
 

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