title: Cannot convert row to model
body: <p>Using JOOQ 3.15, I attempting to map a nested item.</p>
  <pre class="lang-sql prettyprint-override"><code>CREATE TABLE a_table (
      id uuid primary key
  );
  
  
  CREATE TABLE b_table (
      id uuid primary key
  );
  
  CREATE TABLE c_table (
      a_id uuid REFERENCES a_table(id) NOT NULL,
      b_id uuid REFERENCES b_table(id) NOT NULL,
      started_date timestamp with time zone,
      completed_date timestamp with time zone,
      PRIMARY KEY (a_id, b_id)
  );
  </code></pre>
  <p>The classes are just standard POJOs with getters, setters, for above values.</p>
  <p>Then I have a query like:</p>
  <pre class="lang-java prettyprint-override"><code>// aId, and bId are passed in as parameters
  select(
          A_TABLE.asterisk(),
          row(
                  C_TABLE.STARTED_DATE.as(&quot;dateStarted&quot;),
                  C_TABLE.COMPLETED_DATE.as(&quot;dateCompleted&quot;)
          ).as(&quot;c&quot;).convertFrom(r -&gt; r.into(CDomain.class))
  ).from(A_TABLE)
  .leftOuterJoin(C_TABLE)
          .on(C_TABLE.A_ID.eq(A_TABLE.ID).and(C_TABLE.B_ID.eq(bId)))
  .where(A_TABLE.ID.eq(aId))).as(&quot;a&quot;).convertFrom(r -&gt; r.into(ATableRecord.class))
  </code></pre>
  <p>Table <code>C</code>'s entry may be non-existant.</p>
  <p>The error I encounter when I run this code is:</p>
  <pre class="lang-none prettyprint-override"><code>org.jooq.exception.DataTypeException: Cannot convert from class C {
      dateStarted: null
      dateCompleted: null
  } (class com.blah.C_TABLE) to class org.jooq.impl.RecordImpl4
  </code></pre>
  <p>Why is this error occurring? Why is it trying to convert from my class to a record, when I am asking it to convert the record to a class? How could I fix this?</p>