1. It will not get data from DB when just open the cursor, data will be loaded as an ongoing basis.
2. SCN: System Change Number/System Commit Number
3. FLASH BACK AS OF SCN;
4. You can also flash back table: FLASHBACK TABLE SOME_TABLE TO SCN :SCN_NUM;
5. But before you do a flash back operation on a table, do make sure you have already enbale ROW MOVEMENT on that table.