Log record header

   Redo always                                          0x0001
   Propagatable                                         0x0002
   Temp table                                           0x0004
   Table space rollforward undo                         0x0008
   Singular transaction (no commit/rollback)            0x0010
   Conditionally recoverable                            0x0080
   Table space rollforward at check constraint process  0x0100
   Runtime rollback                                     0x0200
   Pseudo compensation                                  0x0800

   A 64-bit identifier that determines the order of the operations
   that generated the log records. The LSN is an ever-increasing value.
   Each member writes to its own set of log files (a log stream),
   and the LSN within a single log stream is a unique number.

   db2LSN: { db2Uint64 lsnU64;
                     }

   A unique log record identifier representing the transaction.

   SQLU_TID: union { unsigned char  [6] ;
                     unsigned short [3] ;
                     }

   A unique number identifying the position of a record.
   RID: Page number 	char [4];
   slot number 	char [2];