在一个典型的XLOG插入中
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfHeapInsert);
xlhdr.t_infomask2 = heaptup->t_data->t_infomask2;
xlhdr.t_infomask = heaptup->t_data->t_infomask;
xlhdr.t_hoff = heaptup->t_data->t_hoff;
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD | bufflags);
XLogRegisterBufData(0, (char *) &xlhdr, SizeOfHeapHeader);
XLogRegisterBufData(0,
(char *) heaptup->t_data + SizeofHeapTupleHeader,
heaptup->t_len - SizeofHeapTupleHeader);
XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
recptr = XLogInsert(RM_HEAP_ID, info);
PageSetLSN(page, recptr);
下图只解释XLogSetRecordFlags前面的数据注册部分。