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POEntity Framework One-To-Many Delete relationship
 

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    <p>I have two entities <code>Transaction</code> and <code>DiscountType</code></p> <p><strong>Transaction:</strong></p> <pre><code>public class Transaction { [Key] public int TransactionID { get; set; } public virtual DiscountType DiscountType { get; set; } } </code></pre> <p><strong>DiscountType:</strong></p> <pre><code>public class DiscountType { [Key] public int DiscountTypeID { get; set; } public virtual ICollection&lt;Transaction&gt; Transactions { get; set; } public float DiscountValue { get; set; } public bool Enabled {get; set;} } </code></pre> <p><strong>Relationship:</strong></p> <pre><code> modelBuilder.Entity&lt;DiscountType&gt;().HasMany(d =&gt; d.Transactions); </code></pre> <p><strong>Aim:</strong></p> <p>I am trying to remove the relationship between the Transaction and the DiscountType, without actually removing either entity.</p> <p><strong>Problem:</strong></p> <p>Now I'm having no problem assigning a Discount to a transaction, but when I do the following:</p> <pre><code> var transaction = context.Transactions.Where(t =&gt; t.TransactionID == 1).First(); transaction.DiscountType = context.DiscountTypes.Where(d =&gt; d.DiscountTypeID == 1).First(); context.SaveChanges(); var _transaction = context.Transactions.Where(t =&gt; t.TransactionID == 1).First(); _transaction.DiscountType = null; context.SaveChanges(); </code></pre> <p>It's quite a peculiar problem I'm having. When this code is ran it does not remove the relationship between the two.</p> <p><strong>Actual Code:</strong></p> <p><img src="https://i.stack.imgur.com/FrLLu.png" alt="As you can see, even after the &lt;code&gt;= null;&lt;/code&gt; is executed, it still remains."></p> <p>As you can see, even after the <code>= null;</code> is executed, it still remains.</p>
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    1. USgunwin
    1. USgunwin
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    1. COI'm a fan of foreign keys for those types of relationships.
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      1. USTravis J
    2. COPlease elaborate. I'm new to EF.
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      1. USgunwin
    3. COHave you tried getting your DiscountType (via the context) and then calling .Remove(yourtransaction) on DiscountType.Transactions? I had to do this for EF because SaveChanges does not recognize changes to relationships - only scalar value changes.
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      1. USJasCav
 

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