code: public OQueryContextNative key(final Object iKey) {
  		if (finalResult != null && finalResult.booleanValue())
  			return this;
  
  		if (iKey == null)
  			// ERROR: BREAK CHAIN
  			return error();
  
  		if (currentValue != null && currentValue instanceof Map)
  			currentValue = ((Map<Object, Object>) currentValue).get(iKey);
  
  		return this;
  	}
docs: Sets as current value the map's value by key.
  
  @param iKey
  Key to use for the lookup
  @return This object to allow fluent expressions in chain.