/ Programming Ib: Lecture
- Be sure to come to revision lecture next week.
- I will talk for ~20
minutes about the unit & the exam
- Those of you who have finished all the coursework should
already have begun revising, and come asking questions.
- Those of you who spent the weekend finishing coursework should
still come & listen to my lecture & my answers to the other
- Be sure to submit all your coursework by Monday, whatever you have
by then, just hand it in.
- It is really pretty easy to get 20% on the coursework.
- It is really a lot easier to
get 60% on the exam than 80%.
- We will try to work out how to get CWs marked if you missed the
I. What You Should Have Learned Last Week
- About relations
- Databases are no longer one big table -- those were redundant
and incomplete at the same time.
- the basic ideas of SQL
- select * from otters
- select * from otters where name = fred
- select age from otters where name = fred
- select name, age into cutenames from otters -- create a new table
that's a subset of the big table
- select * from otters, habitatregions where otter.habitat =
- select * from otters, habitatregions hr where otter.habitat =
- this can get arbitrarily
- Some people have trouble thinking about this, but
- this is how you reconstruct your big tables out of properly
relational databases so it really should be intuitive.
that AI really works and is in a lot of our technology
- update otters set health = fine where name = fred
- update otters set health=hazard from otters, habitatregions hr
where otter.habitat =
- Django was doing a lot for you.
- It can't hold a conversation or prove it's concious, but
neither can chimpanzees.
II. How Do You Save Things Forever?
- There's no point in storing data somewhere if you can't be sure
it's going to be there in the morning.
- This is an outline of a bunch of slides I showed you:
selected highlights of the database course I wrote (and you'll get next
- What kind of threats are there?
- Where do you physically store your data?
- How can you be sure your data is really safe?
- How can you change your data and still know it's OK?
- This has to do with transactions and logging.
- This is very related to Corruption
Locking & Synchronisation in Lecture 8.
- Here are the slides.
- You can never be sure that your data is safe, but there are a lot
of ways to make it safer.
- Be sure to start studying before the revision lecture on Tuesday
so you have questions.
page author: Joanna Bryson
6 May 2010