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PO
 

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  1. PO
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    <p>I think your problem is happening because you're creating a new <code>MedicineInventory</code>.</p> <p>Replace this:</p> <pre><code>MedicineInventory toRemove = new MedicineInventory(); </code></pre> <p>With this:</p> <pre><code>var toRemove = ctx.MedicineInventories.Single(mi =&gt; mi.MedicineInventoryId == Mid); </code></pre> <p><strong>Update:</strong></p> <p>When it retuns the error message <em>"Sequence contains no elements"</em> it's because EF could not find a row in the database with the same Guid you're using in the <code>where</code> clause. In this case and to avoid an exception, you can try this line of code:</p> <pre><code>var toRemove = ctx.MedicineInventories.SingleOrDefault( mi =&gt; mi.MedicineInventoryId == Mid); </code></pre> <p>then use an <code>if</code> to delete if it's not <code>NULL</code>:</p> <pre><code>if(toRemove != null) { ctx.MedicineInventories.Remove(toRemove); ctx.SubmitChanges(); } else { // Only you know what to do! :-) } </code></pre> <blockquote> <p><a href="http://msdn.microsoft.com/en-us/library/bb342451.aspx" rel="nofollow">SingleOrDefault</a> returns the only element of a sequence, or a default value (<code>NULL</code> in this case) if the sequence is empty; this method throws an exception if there is more than one element in the sequence.</p> </blockquote> <hr> <p>Note: the way you're comparing the Guids is correct because <code>==</code> is overloaded on Guid so you don't need to compare the string representations.</p> <p>See <a href="http://msdn.microsoft.com/en-us/library/system.guid.op_equality%28v=vs.110%29.aspx#Y474" rel="nofollow">http://msdn.microsoft.com/en-us/library/system.guid.op_equality%28v=vs.110%29.aspx#Y474</a></p>
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    1. USLeniel Maccaferri
    1. USLeniel Maccaferri
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    1. COI now get a "Sequence contains no elements" error...
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    2. COAre you absolutely sure that your table on the database has a `MedicineInventory` with the same Guid you're passing in the query? Put a breakpoint in the line of code I mention in my answer and take note of the Guid and compare it with the one you have on the database side.
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    3. COI am yes. They both have the same Guid. Is there perhaps something that i need to change in the metadata that's inhibiting the removal?
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      1. USuser1732039
 

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