docs: public String getOuterMostNullEmbeddableIfAny(String column) {
  		String[] path = column.split( "\\." );
  		if ( !isEmbeddableColumn( path ) ) {
  			return null;
  		}
  		// the cached value may be null hence the explicit key lookup
  		if ( columnToOuterMostNullEmbeddableCache.containsKey( column ) ) {
  			return columnToOuterMostNullEmbeddableCache.get( column );
  		}
  		return determineAndCacheOuterMostNullEmbeddable( column, path );
  	}