// Open the storage subsystem.
    void open_storage()
    {
      EXEC SQL BEGIN DECLARE SECTION;
      const char* database = DATABASE_NAME;
      const char* username = USERNAME;
      const char* schema = SCHEMA;
      EXEC SQL END DECLARE SECTION;

      EXEC SQL WHENEVER SQLERROR CALL quit();
      EXEC SQL CONNECT TO :database USER :username;
      EXEC SQL SET search_path to :schema;
    }

My takeaway was that it was a lot easier than I expected, but it was still kind of a minefield. ECPG isn't widely used or highly intelligent, so there are a lot of stumbling blocks despite the pretty high quality documentation. I would recommend hiding your ECPG behind some functions so you only have to run some of your files through the pre-processor. But it is a neat tool and I could see myself using it again.