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POFluent NHibernate: Custom ForeignKeyConvention not working with explicitly specified table names
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copied!<p>EDIT: for the tl;dr crowd, my question is: How do I access the mappings from inside the ForeignKeyConvention in order to determine the table name that a given type is mapped to?</p> <p>The long version:</p> <p>I am using Fluent NHibernate to configure NHibernate, and I have a custom foreign key convention that is failing when I alias tables and columns. </p> <p>My tables use a convention where the primary key is always called "PK", and the foreign key is "FK" followed by the name of the foreign key table, e.g., "FKParent". For example:</p> <pre><code>CREATE TABLE OrderHeader ( PK INT IDENTITY(1,1) NOT NULL, ... ) CREATE TABLE OrderDetail ( PK INT IDENTITY(1,1) NOT NULL, FKOrderHeader INT NOT NULL, ... ) </code></pre> <p>To make this work, I've built a custom ForeignKeyConvention that looks like this:</p> <pre><code>public class AmberForeignKeyConvention : ForeignKeyConvention { protected override string GetKeyName( Member member, Type type ) { if ( member == null ) return "FK" + type.Name; // many-to-many, one-to-many, join return "FK" + member.Name; // many-to-one } } </code></pre> <p>This works so long as my entities are named the same as the table. But it breaks when they aren't. For example, if I want to map the OrderDetail table to a class called Detail, I can do so like this:</p> <pre><code>public class DetailMap : ClassMap<Detail> { public DetailMap() { Table( "OrderDetail" ); Id( o => o.PK ); References( o => o.Order, "FKOrderHeader" ); ... } } </code></pre> <p>The mapping works for loading a single entity, but when I try to run any kind of complicated query with a join, it fails, because the AmberForeignKeyConvention class is making incorrect assumptions about how the columns are mapped. I.e., it assumes that the foreign key should be "FK" + type.Name, which in this case is Order, so it calls the foreign key "FKOrder" instead of "FKOrderHeader".</p> <p>So as I said above: My question is, how do I access the mappings from inside the ForeignKeyConvention in order to determine a given type's mapped table name (and for that matter, their mapped column names, too)? The answer to <a href="https://stackoverflow.com/questions/2292051/can-i-make-a-fluent-nhibernate-foreign-key-convention-which-includes-parent-key">this question</a> seems to hint at the right direction, but I don't understand how the classes involved work together. When I look through the documentation, it's frightfully sparse for the classes I've looked up (such as the <a href="http://fluentnhibernate.org/api/FluentNHibernate.MappingModel.Identity/IdMapping.htm" rel="nofollow noreferrer">IdMapping class</a>).</p>

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