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POvery slow conversion of query to list
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  1. POvery slow conversion of query to list
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    copied!<p>I'm querying from a single view to retrieve a list of indicators. All the properties of an indicator can be retrieved from that single view.</p> <p>Here's the code:</p> <pre><code>data = new DataContext(); var core = from item in data.Items where countryIDs.Contains(item.CountryId) &amp;&amp; indicatorIDs.Contains(item.IndicatorId) orderby item.Indicator select item; var x = from item in core.Distinct() group item by new { item.IndicatorId, item.Indicator } into indicator select new { IndicatorID = indicator.Key.IndicatorId, IndicatorDescription = indicator.Key.Indicator, Genders = from g in core where g.Gender != null &amp;&amp; g.IndicatorId == indicator.Key.IndicatorId select new Gender { GenderID = g.GenderId, GenderDescription = g.Gender }, HasGender = (from g in core where g.Gender != null &amp;&amp; g.IndicatorId == indicator.Key.IndicatorId select g.GenderId).Count() &gt; 0, AreaTypes = from rat in core where rat.IndicatorId == indicator.Key.IndicatorId &amp;&amp; rat.AreaType != null select new AreaType { AreaTypeId = rat.AreaTypeId, AreaDescription = rat.AreaType }, HasAreaType = (from rat in core where rat.IndicatorId == indicator.Key.IndicatorId &amp;&amp; rat.AreaType != null select rat.AreaTypeId).Count() &gt; 0, Sectors = from s in core where s.IndicatorId == indicator.Key.IndicatorId &amp;&amp; s.Sector != null select new Sector { SectorID = s.SectorId, Title = s.Sector }, HasSector = (from s in core where s.IndicatorId == indicator.Key.IndicatorId &amp;&amp; s.Sector != null select s.SectorId).Count() &gt; 0 }; List&lt;Indicator&gt; indicators = new List&lt;Indicator&gt;(); Indicator i = new Indicator(); foreach (var item in x) { i = new Indicator() { IndicatorID = item.IndicatorID, IndicatorDescription = item.IndicatorDescription, Genders = item.Genders.ToList(), AreaTypes = item.AreaTypes.ToList(), Sectors = item.Sectors.ToList(), HasGender = item.HasGender, HasAreaType = item.HasAreaType, HasSector = item.HasSector }; indicators.Add(i); } return indicators; </code></pre> <p>It slows down when it reaches the foreach loop, when x is transformed. Is there any way to make this query convert to a list faster? Thank you.</p>
 

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