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POSaving to a many to many relationship
 

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    <p>The problem am facing is, anytime I call events.Tags.Add(tag) and call Save changes on the context, it ends up creating a new tag info in the Tags table instead of just inserting the EventId and TagId into just the EventTags Table.</p> <p>Base on the data below how do I add an event and tag into the EventTags Table. Lets say I want to add Event with Id=2 and and tag with Id =1 to the EventTags table.</p> <p>I have the following entities.</p> <pre><code> public class Event { public int Id { get; set; } public string Name { get; set; } public virtual ICollection&lt;Tag&gt; Tags { get; set; } } public class Tag { public int Id { get; set; } public string Name { get; set; } public virtual ICollection&lt;Event&gt; Events { get; set; } } public class EventConfiguration : EntityTypeConfiguration&lt;Event&gt; { public EventConfiguration () { ToTable("Events"); HasKey(x =&gt; x.Id).Property(x =&gt; x.Id).HasColumnName("Id").IsRequired(); Property(x =&gt; x.Name).HasColumnName("Name").IsRequired(); HasMany(x =&gt; x.Tags) .WithMany(x =&gt; x.Events) .Map(m =&gt; { m.ToTable("EventTags"); m.MapLeftKey("EventId"); m.MapRightKey("TagId"); }); } } public class TagConfiguration : EntityTypeConfiguration&lt;Tag&gt; { public TagConfiguration () { ToTable("Tags"); HasKey(x =&gt; x.Id).Property(x =&gt; x.Id).HasColumnName("Id").IsRequired(); Property(x =&gt; x.Name).HasColumnName("Name").IsRequired(); } } /* These are the records in my many to many tables -------------- Events Table -------------- Id Name 1 Test1 2 Test2 -------------- EventTags ------------- EventId TagId 1 2 ------------- Tags ------------ Id Name 1 MVC 2 C# */ </code></pre>
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    1. COpost your add code - is the tag you are adding fetched from the same DBContext ?
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Guidance
A row detail

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.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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