INFO 340 - June 2, 2004 - L19
Notes By: Prins

** No Lab on Friday **

D-Space (MIT)
    > Open source software platform that enables institutions to:
        - Capture and describe digital works
        - Distribute an institution's digital works over the web through a search and retrieval system
        - Preserve digital works over the long term

separated into three layers
    Storage Layer
    Business Logic Layer
    Application Layer

Final Examination
Monday, June 7th, 2:30 - 4:20
Covers the Entire Course

Today: Quick reminder of Key Topics

    > Systems
        - processes
        - inputs
        - outputs
        - entities
        - stakeholders
        - environment (is up to you to define)

Three Key Ideas
    > Systems are hierarchal
    > Systems are nearly decomposable
    > System boundaries are arbitrary

** Development Life Cycle **
    Define
    Design
    Develop ** OUR FOCUS IN CLASS **
    Deploy

Three Phases
    1. Conceptual database design
        The process of constructing a model of the information used in the enterprise.....
    2. Logical database design
        > The process of constructing a model of the information used in the enterprise based on a specific data model, but independent of a particular DBMS and other physical considerations
        > Key Idea: 'Translate' conceptual model into abstractions into target database
    3. Physical database design
       >  The process of producing a description of the implementation of teh database on secondary storage;
            - Base relations & Views
            - File organization
            - Indexes
            - Integrity constraints
            - Security measures
       > Key Idea: Performance & engineering issues
       > Big Issue: Keep data consistent and backed up

Relational Model
    > Background
        - History, users, roles ...
    > DBMS Environment
        - Three-Level architecture, data models, data independence, functions, services, ...
    > The relational model
        - relations, keys, DML, DDL, SQL, integrity constraints, relational algebra.
    > Relational design
        - ER & EER modeling, connection traps, functional dependencies, normalization, ...

IR vs Relational Database
    > IR Systems and Relational Database systems come from different cultures
    > They have traditionally solved different problems
    > How can we compare the two approaches?

Exercise
    > What is the difference between IR and database systems?
        - Data structures used (inverted file vs trees)
        - Different Services
        - Storage of Data (data redundancy in indexes, but not well designed DB)
        ----- From Slide ----- (DB vs IR)
        - Matching (Exact Match vs Partial match, Best match)
        - Inference (Deduction vs Induction)
        - Model (Deterministic (know specification for right answers) vs Probabilistic (based on probability))
        - Classification (Monotheistic vs Polytheistic)
        - Query Language (Artificial vs Natural)
        - Query Specification (Complete vs Incomplete)
        - Items wanted (Matching vs Relevant)
        - Error response (Sensitive vs Insensitive)






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oh. my. god. Becky, look at her butt! Its like one of those rappers' girlfriends. She must be a slut... OMGWTFBBQ

Let's make a Baby! - Watch the Anchorman trailer @ quicktime.com
    heh, seen it on the big screen, funny stuff
    no, there is a new one :) from the 30th
    ooh...
    did either of you catch that video of that guy who stuck a camera on his car and sped it up, 9 hours of trip into 5 minutes? it was on slashdot yesterday
    I havent looked at the internet for a while
    lol
    blah blah blah kill me
    yeah I'm totally wrong, but will I speak up? hell no
    I think I might go home at the break... this is useless or not.