Databases
StackOverflow2013
Postsdbo
PO(Fluent) NHibernate: Map field from separate table into object
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO(Fluent) NHibernate: Map field from separate table into object
    primarykey
    data
    text
    <p>I'm currently trying to get (Fluent)NHibernate to map an object to our legacy database schema. There are three tables involved. </p> <ul> <li>Table a contains most information of the actual object I need to retrieve</li> <li>Table b is a table which connects table a with table c</li> <li>Table c has one additional field I need for the object</li> </ul> <p>An SQL query to retrieve the information looks like this:</p> <pre><code>SELECT z.ID, z.ZANR, e.TDTEXT FROM PUB.table_a z JOIN PUB.table_b t ON (t.TDKEY = 602) JOIN PUB.table_c e ON (e.ID = t.ID AND e.TDNR = z.ZANR) WHERE z.ZANR = 1; </code></pre> <p>The main problem is how to specify these two join conditions in the mapping.</p> <p>Entity for table a looks like this:</p> <pre><code>public class EntityA { public virtual long Id { get; set; } public virtual int Number { get; set; } public virtual string Name { get; set; } } </code></pre> <p>Name should map to the column table_c.TDTEXT.</p> <p>The mapping I have so far is this:</p> <pre><code>public class EntityAMap : ClassMap&lt;EntityA&gt; { public EntityAMap() { Table("PUB.table_a"); Id(x =&gt; x.Id).Column("ID"); Map(x =&gt; x.Number).Column("ZANR"); } } </code></pre> <p>I tried to map the first join with the same strategy as in <a href="https://stackoverflow.com/questions/1241005/how-to-join-table-in-fluent-nhibernate">How to join table in fluent nhibernate</a>, however this will not work, because I do not have a direct reference from table_a to table_b, the only thing connecting them is the constant number 602 (see SQL-query above).</p> <p>I didn't find a way to specify that constant in the mapping somehow.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. UScguedel
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COWhat do your entities look like? What mapping have you tried so far?
      singulars
      1. PO(Fluent) NHibernate: Map field from separate table into object
      1. USPaul Turner
 

Querying!

 
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.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload