title: Apache databaseConfiguration doesn't work with MapConfiguration
body: <p>I am trying to combine both mapConfiguration(file with properties) with databaseConfiguration. However only the file properties can be looked up but not the database properties. What am I doing wrong?</p>
  
  <pre><code>public class MapConfigProvider extends ConfigurationProvider {
      Map properties = null;
      public MapConfigProvider(Map inProps) {
          super(MapConfiguration.class);
          properties = inProps;
      }
  
      @Override
      public AbstractConfiguration getConfiguration(ConfigurationDeclaration decl) throws Exception {
          MapConfiguration mapConfig = new MapConfiguration(properties);
          return mapConfig;
    }
  }
  </code></pre>
  
  <hr>
  
  <pre><code>public class DatabaseConfigurationProvider extends ConfigurationProvider {
      private DatabaseConfigDef dbConfigDef;
  
    public DatabaseConfigurationProvider(DatabaseConfigDef databaseConfigDef)
    {
      super(DatabaseConfiguration.class);
      this.dbConfigDef = databaseConfigDef;
    }
  
    public DatabaseConfigurationProvider() {
      super();
    }
  
    @Override
    public AbstractConfiguration getConfiguration(ConfigurationDeclaration decl) throws Exception {
          DataSource ds = DataSourceFactory.getInstance().getDataSource(DATASOURCE.SEMS);
          return new DatabaseConfiguration(ds, "CSW_TABLE",  "PROP_COL", "VALUE_COL"); //String values sought from databaseConfigDef
    }
  }
  </code></pre>
  
  <hr>
  
  <pre><code>private static final Map&lt;String, Object&gt; propertiesMap= new HashMap&lt;String, Object&gt;();
  
  DefaultConfigurationBuilder builder = new DefaultConfigurationBuilder(propFileUrl);
  
  builder.addConfigurationProvider("filebased", new MapConfigProvider(propertiesMap));
  
  builder.addConfigurationProvider("ctkdatabase", new DatabaseConfigurationProvider(databaseConfigDef));
  
  CombinedConfiguration combinedConfig = builder.getConfiguration(true);
  
  String prop1 = combinedConfig.getString("WCM_WEBSERVICE_PORT");  //From DB, gets null
  String prop2 = combinedConfig.getString("temp"); //From file, fetches good
  LOGGER.info(prop1 + prop2); 
  </code></pre>
  
  <p>What am I doing wrong? Please help.</p>