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    <p>What you are getting is the default behavior of EF Code First in terms of mapping a 1 to Many association to the database. For example you have a <code>ICollection&lt;File&gt;</code> on Person class, as a result, EF will create a FK on Files table (PersonId) and map it to Id PK on Persons table. <br><br> Now, my guess is that you like to have a <em>many to many</em> relationship between File and Person, so that each file can relates to many Persons and each Person can have many files (same story for Event object as well). One way to achieve this is to put navigation properties on File class pointing to Event and Person classes. So, your model should be changed to this:</p> <pre><code>public class File { public int Id { get; set; } public string Path { get; set; } public virtual ICollection&lt;Event&gt; Events { get; set; } public virtual ICollection&lt;Person&gt; Persons { get; set; } } public class Event { public int Id { get; set; } public string EventName { get; set; } public virtual ICollection&lt;File&gt; Files {get;set;} } public class Person { public int Id { get; set; } public string Name { get; set; } public virtual ICollection&lt;File&gt; Files { get; set; } } public class MyContext : DbContext { public DbSet&lt;Person&gt; Persons { get; set; } public DbSet&lt;Event&gt; Events { get; set; } public DbSet&lt;File&gt; Files { get; set; } } </code></pre> <p>As a result, EF will create link tables (Events_Files and Files_Persons) to map these many to many associations to the database.</p> <p><strong>Update:</strong> <br> When using POCOs with EF, if you mark your navigation properties as <em>virtual</em> you will opt-in to some of the additional EF supports like <em>Lazy Loading</em> and <em>Relationship Fixup</em>. So in general have a virtual keyword in navigation properties considered to be a good practice.</p>
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    1. POHow to have Many to Many Association in Entity Framework Code First
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    1. USMorteza Manavi
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    1. COI'm pretty sure for the link table (File class), it should be "public virtual Events" instead of ICollection. Btw, I knew about navigation properties, but didn't know about the virtual keyword. Good tip. Thx.
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    2. COWhen using the example above, creating a new relation also adds a new item in the related table. So in this case you have File and do the following: File.Events = new Eventlist (where eventlist is populated with events retrieved from the database) the db.savechanges adds not only the relationship record in Events_Files but also an event in Events table. What should be a proper way to add a relationship record in events_files but not an extra record in events.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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