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    copied!<p>If you look at the MSDN here: <a href="http://msdn.microsoft.com/library/vstudio/bb896325" rel="nofollow">http://msdn.microsoft.com/library/vstudio/bb896325</a> </p> <blockquote> <p>The Entity Framework opens connections only when required, for example to execute a query or to call SaveChanges, and then closes the connection when the operation is complete. </p> <p>When a query method is called, the connection is opened, and it remains open until the ObjectResult has been completely consumed or disposed.</p> </blockquote> <pre><code>public void UpdateCategory(Models.Category catData) { if (catData == null) return; using (var cntx = new DataContext()) { //IN THE LINE BELOW A CONNECTION IS DEFINITELY OPENED BUT IS IT //IMMEDIATELY CLOSE? =&gt; YES! var cat = cntx.Set&lt;Category&gt;() .FirstOrDefault(c =&gt; c.CategoryId == catData.CategoryId); if (cat == null) return; if (!cat.LastChanged.Matches(catData.LastChanged)) throw new ConcurrencyException(cat.GetType().ToString()); cat.CategoryName = catData.CategoryName; cntx.DbContext.Entry&lt;Category&gt;(cat).State = System.Data.EntityState.Modified; //AFTER THE NEXT LINE DO I HAVE 2 CONNECTIONS OPENED? =&gt; NO cntx.SaveChanges(); catData.LastChanged = cat.LastChanged; } } </code></pre> <blockquote> <p>Are there scenerios where the same context creates\opens 2 connections, leaving one open?</p> </blockquote> <p>Yes, when using transaction with a DbContext it will open a second connection have a look here: <a href="http://www.digitallycreated.net/Blog/48/entity-framework-transactionscope-and-msdtc" rel="nofollow">http://www.digitallycreated.net/Blog/48/entity-framework-transactionscope-and-msdtc</a></p>
 

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