title: logback: DBAppender not writing to logging_event_exception
body: <p>I have the following logback.xml configuration</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;configuration&gt;      
      &lt;appender name = "DB" class="ch.qos.logback.classic.db.DBAppender"&gt;
          &lt;connectionSource class="ch.qos.logback.core.db.DriverManagerConnectionSource"&gt;
              &lt;driverClass&gt;com.microsoft.sqlserver.jdbc.SQLServerDriver&lt;/driverClass&gt;
              &lt;url&gt;jdbc:sqlserver://servername:1433;databaseName=dbname&lt;/url&gt;
              &lt;user&gt;user&lt;/user&gt;
              &lt;password&gt;pass&lt;/password&gt;
          &lt;/connectionSource&gt;
      &lt;/appender&gt;                
      &lt;root&gt;
          &lt;level value="debug" /&gt;
          &lt;appender-ref ref="DB" /&gt;        
      &lt;/root&gt;
  &lt;/configuration&gt;
  </code></pre>
  
  <p>and was expecting this simple test to create an entry in the logging_event_exception table:</p>
  
  <pre><code> public static void main(String[] args) {
          Logger logger = LoggerFactory.getLogger(MyClass.class);
          try {
              throw new RuntimeException("some error");
          } catch (RuntimeException e) {
              logger.error("test");
          }
  
  
      }
  </code></pre>
  
  <p>but it only inserts an entry into the logging_event_table.
  What am I missing in the configuration?</p>
  
  <p>Thanks.</p>