EMA C++ RDM Usage Guide : 8 Market By Price Domain : 8.3 Data : 8.3.2 Summary Data
 
8.3.2 Summary Data
The Map.SummaryData needs to be present only for the first refresh part, which typically includes:
Permission information (PROD_PERM)
Currency of the orders (CURRENCY)
Trade Units for the precision with which order prices are set (TRD_UNITS)
Market State (MKT_ST_IND)
The identifier of the exchange on which the orders were placed (RDN_EXCHD2)
Price Ranking Rules (PR_RNK_RUL)
Quote Date (QUOTE_DATE)