The Incredible Flashback Data Archive скачать в хорошем качестве

The Incredible Flashback Data Archive

Chris Saxon explores Flashback Data Archive: what it's for, how to use it, and why you can get ORA-01405 errors when querying it. We also looked at how to use SQL to report overlapping date periods, show all the rows in a time period. This covered unpivoting and recursive solutions, comparing the performance of the two. Highlights include: Flashback 2:00 The problem of fraud and the need for auditing to detect it 8:10 Flashback query; how you can use this to see changes; the limiations with this 10:45 How to enable Flashback Data Archive 12:30 Flashback Data Archive demonstration SQL: Merging overlapping dates 30:00 The problem: breaking overlapping from/to date periods into all the possible sub-periods 32:30 How to solve this; pivoting from/to dates, then generating all the subperiods 33:40 A walk through the SQL 38:40 The SQL in action; a discussion of it's performance and comparison to other methods 50:00 How to get exeuction plans in SQL Developer and compare two plans, side-by-side