code: @SafeVarargs
    public static void
    takeSnapshot(DataSource... dataSources)  {
      ensureDistinctDataSources(dataSources, Function.identity());
      foreach(dataSources, 
             (callInfo, dataSource) -> dataSource.executeQuery(callInfo, true), 
             CallInfo.create());
    }
docs: Take a database snapshot for several data sources.
  
  @param dataSources Data sources.
  
  @see #takeSnapshot(DataSource)
  @since 1.2