Title: Vision and Politics
1Vision and Politics
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2- A. Silberschatz, M. Stonebraker, J. Ullman,
"Database Research Achievements and
Opportunities Into the 21st Century," ACM SIGMOD
Record, March 1996.
3summary of the workshop held in May of 1995
Points of interest
- Key role in creating techonological
infrastracture - Areas of database research support for
multimedia objects, distribution of information,
new database applications, workflow and
transaction management, and ease of database
management and use. - New capabilities provided by the technology
developments in hardware capability, hardware
capacity, and communication. - ? need for industrial support
42 themes ? of demand require new
solutionshistorically confirmed of ability to
put ideas to practical useso viability of db
research community vital
5The Changing World of Database Management
- A db system is a computerized record keeping
system - Stores provides access to information
- Basic components data hardware shoftware
- (consideration scope magnitude complexity)
- Hardware inpact ? cost ? speed components
(multiprocessors) ? capacity - Every humal enterprise includes computerized info
6The Case for DBMS Research
- Goal of this report
- financial support of db research is a worthwhile
investment - Illustrating the pay off from funding db research
7Recent Research Achievements
- in 1990 report the grate majority of market are
US-owned companies - products from research prototypes
- outline of the new developments
8Object-Oriented and Object-Relational Database
Systems
- In 1990 few research prototype of OODBs.
- Questionable relationship of OODBs and relational
systems - Few research prototypes combining features of
relational DBMS (SQL access to simple data types)
with OODBs (modelling of complex data) to create
ORDBs (object relational database systems) and
DOODs (deductive object oriented database
systems) - Today there are a variety of commercial OODBs
-
- It is a 75M/year market growing at about 50 per
year.
9Support for New Data Types
- Research attempts of last decade concerning
spatial and temporal data types are now part of
commercial DBMSs and GIS
10Transaction Processing
- A DBMS support coordination of many users of
shared information - Traditional transaction management not enadequate
for todays distributed information systems
11New db Applications
12EOSDISEarth Observing System Data Information
System
- EOS is a collection of satellites gathering info
regarding atmosphere, oceans and land. They
return 1/3 PentaByte/year of data that are
integrated in EOSDIS. - Challenges are
- Providing on-line access to PB-sized Databases
- Supporting thousands of information consumers
- Providing effective mechanisms for browsing and
searching for the desired data
13Electronic Commerce
- There are thousands of projects supporting
electronic purchasing of goods. E-commerce
involves very large number of participants
interacting over the network. - Unlike EOSDIS there are many suppliers and many
consumers. Among the challenges are - Heterogeneous information sources must be
integrated - E-commerce needs reliable, distributed
authentication and funds transfer
14Health Care Information Systems
- Physicians need to draw on different kinds of
info like - Medical records on various hospitals
- Info about drugs
- Procedures
- Diagnostic tools
- Transforming health-care sector will have major
impact on cost and quality. Challenges are - Integration of heterogeneous forms of information
- Access control to preserve confidentiality of
medical records - Interfaces to information appropriate for
health-care professionals
15Digital Publishing
- Storage of books articles in electronic form
and delivery through high speed networks offering
new features like audio video. - Education industry draws much closer ro
publishing and offers facilities like interactive
learning. Challenges are - Management and delivery of extremely large bodies
of data at very high rates - Protection of intellectual properties
16Trends That Affect Database Research
- Technological Trends
- the last 50 years exponential improvement
- Improvement by factor 10 every 10 years on
- of machine instruction executable in a
sec - processor cost
- amount of secondary storage per unit
cost - amount of main memory per unit cost
- Improvement in price/performance ? new products,
services - The last few years
- bits transmitted / unit cost
- bits transmitted / sec
- so able to deal with Terabytes, complex queries
cost effectively
17Database Architecture Trends
- changes in db structure and use
- The relational approach is today ubiquitous (from
very large parallel architectures to home
computers) - Client-server architectures will become
progressively more common for database servers to
be accessed remotely over networks. - The traditional data has been joined by various
kinds of multimedia data. This trend is fuelling
the success of ORDB
18Information Highway
- of Web bits carried by the Internet ? 15-20
per month, or a factor of 10 growth per year. - db will play a critical role in this information
explosion.
19New Research Directions
- Putting multimedia objects to DBMSs
- Distribution of information
- New uses of db
- New transaction models
- Easy use and management of db
20Support for Multimedia Objects
- Areas of research in multimedia data
- Tertiary Storage
- new level of storage hierarchy
- is made by buffering selected data to
secondary storage like acess to secondary storage
by buffering selected data to main memory from
disk - Tertiary storage devices are orders of magnitude
slower than secondary storage(disks), yet also of
vastly greater capacity.
21Support for Multimedia Objects
- New Data Types
- To support multimedia objects
- QoS
- delivering multimedia data to many users
- bottleneck
- different needs (movie/ lecture video)
- optimize access based on predicted use
22Support for Multimedia Objects
- User Interface Support
- Requirenment of new interface other than SQL
- Ex Quering image db need interface that allows
description of color, shape, other
characteristics - For ex. Course video sample frames, text-based
indexes, segment search
23Distribution of Information
- new environment facilitated by the Web requires
rethinking of the concepts in current distributed
database technology - Degree of autonomy
- Db sources connected through a network owned by
different participants (health care system Web) - Refuse connection
- Different systems capabilities
- Accounting and Billing
- Client payments for each access to remote data
- Quering strategies- billing rates. Willing?
24Security and Privacy
- Flexible authentication and authorization systems
- Sale information of anonymous user
25Replication and Reconciliation
- Nodes disconnected
- Data often duplicated
- Copies reconciled at connection
- Frequent event
- Need for high speed protocols algorithms
- Ex call routing system
26Data Integration and Conversion
- Information sources has a variety of formats and
models - Use of mediators like agents
27Information Retrieval and Discovery
- problems
- ? information of informally connected sources /
heterogeneous data - Changes without notice
- Unclear definitions
- Need for techniques to support searches like in
db technology (indexes)
28Data Quality
- Different sources with different reliability
- Evaluate and query the reliability or the lineage
(origin)
29- Extraction of information from large bodies
- Decision makers
- Fast response
- Formulate query
- Optimization techniques for complex queries
- Use of non expert users
30Data Warehouses
- Huge collections of data mainly used for decision
support systems. They copy of data from one or
more databases. - Issues
- Tools for data pumps (modules for obtaining
updates/ translate them) - Methods for data scrubbing (data consistent
identify different representation of the same
value) - Create metadictionary (how data obtained)
31Repositories
- storing and managing both data and metadata
- They must
- Obtain an evolving set of representations of the
same or similar information (module represented
as source code, object code, flow diagram etc..) - Support versions (snapshots of an element
evolving over time) and configurations (versioned
collection of versions)
32Easy of use
- Improved interfaces for end user and application
programmer- administrator - Easier installation and upgrade of db management
systems
33Database MetatheoryAsking the Big
QueriesChristos H. PapadimitriouUniversity
of California San Diego
34Theory and its Function
- In the context of an applied science, theory in
broad sense is the use of significant
abstraction, scientific research, the suppression
of low-level details of the object or artifact
being studied or designed.
35Solution to complexity imposed by theoreticians
- (a) They develop mathematical models of the
artifact. Turing machines, formal languages, and
the relational model
36Solution to complexity imposed by theoreticians
- (b) abstract models can become reality
(typically, algorithms and representational
schemes) that are derived from the mathematical
models.This function of theory is what we usually
mean by synthesis or positive results.Such
results must be actually verified by experiments.
37Solution to complexity imposed by theoreticians
- (c) Analyze the mathematical models to predict
the outcome of the experiments (and calibrate the
models).
38Solution to complexity imposed by theoreticians
- (d) explore. They develop and study extensions
and alternative applications of the model, and
they seek its ultimate limitations. - Introduce and apply more and more sophisticated
mathematical techniques. - build a theoretical body of knowledge and a
mathematical methodology that overcome the
motivating artifact and model - Exploration is usually guided by aesthetics,
taste, and sense of what is important and
relevant.
39uncontroversial necessary parts of the research
and discovery process in any science of the
artificial
- (a)Model building
- (b) synthesis
- (c) analysis
- criticized most predictably
- liked by theoreticians exploration
40arguments in defense of exploration
- (1) It has been historically beneficial to
computer science - (2) in reasonable doses, it promotes the fields
health and connectivity - (3) exploration and proving elegant theorems are
natural and attractive activities, and so it
would be wrong and futile to repress them.
41Drawbacks
- can disortent the field and lead at into crisis,
when it is disproportionately extensive in
comparison to model budding, synthesis, and
analysis - (2) will not thrive if it consistently ignores
practice - (3) requires true discipline and honesty in its
exposition, especially in avoiding frivolous and
unchecked claims of relevance and applicability.
42On Negative Results
- In computer science theorems are judged by (as in
mathematics) - Elegance
- Depth
- importance in long-term research
- But here also
- complexity-reducing or points out a setback in
this regard. -
43- negative results are the only possible
self-contained theoretical results - Positive results complexity reducing solutions
such as algorithms and presentation schemes must
be validated experimentally and can therefore be
considered as mere invitations to experiment. - delimitation is the ultimate success in
exploration
44What is Good Theory?
- Paul Feyerabend
- Science is an essentially anarchic
enterprise. There is no idea that is not
capable of improving our knowledge. The only
principle that does not inhibit progress is
anything goes.
45What is Good Theory?
- although there is no such thing as bad science,
success is an important aspect - Not just an inner process driven by methodology
and results but a much more complex predicate of
the social dynamics of the field and its
environment, and of course open to circumstances
and chance. - An adoption metaphor in computer science from
other sciences is essential and increases its
prestige and propagandistic value.
46What does this all mean for theoreticians?
- free-style exploratory theoretical research
- its success will depend mainly on its
propagandistic value, ability to
contaminate its environment, - especially on its potential to influence
practice - Theoreticians should be expositor and popularizer
to bring his or her results to the attention of
the experimentalist and the practitioner, to
convince them of their value by arguments that
are measured, rigorous, and credible
47What does this all mean for theoreticians?
- do your own experiments helps a lot
- ultimate success of a scientific idea is, of
course, the launching of a victorious scientific
revolution
48Paradigms and Revolution
49The stages of the scientific process according to
Thomas Kuhn for natural science
Immature science
Normal science
Crises
Revolution
50The stages of the scientific process according to
Thomas Kuhn for natural science
Immature science
Normal science
Crises
Revolution
- long periods of normal science, in which the
field progresses incrementally within a broadly
accepted framework that includes not only
scientific assumptions and theories, but also
conventions about what are appropriate questions - to ask and how further development should
proceed. Such a framework is called a paradigm.
Copernicus model and Einsteins general theory
seem to be the most frequently mentioned
paradigms. - scientists consider it their duty to defend the
paradigm and show that it works
51Natural Science
- But cruel facts that do not fit in the paradigm
accumulate, despite the communitys ingenious
efforts to sweep them under the rug the paradigm
creaks and staggers, and we enter a stage of
science in crisis - ?ew kinds of ingenuity and imagination develop
and compete. Eventually, and typically, one of
them triumphs and becomes the next paradigm this
is the stage of scientific revolution - ultimate success of a scientific idea is, of
course, the launching of a victorious scientific
revolution
52Immature science
Normal science
Crises
Revolution
53adaptation to applied science and the sciences of
the artificial.
- Kuhns model ? static / eternal
- in the sciences of the artificial study
artifacts, which keep changing while studied or
because it is being studied - tight closed-loop interaction between a science
and its object. - in case of computer science stages of Kuhns
model are much accelerated -
- Crises in natural science are caused by the
accumulation of anomalies, observations of the
objective reality that cannot fit the current
paradigm. In contrast, in computer science we
have no objective reality against which to judge
our scientific work.
54the operational analog of falsifiability in
computer science
- research units (researchers, papers, research
groups, results,or subfields) influence each
other - Connection
- Autistic behavior is the exception that tests the
wisdom of the rule - Most of theory is within a few hops from
practice, and vice-versa.
55- bottom snapshot
- local situation seems unchanged (say, the average
degree is the same) - connectivity is low
- Tangents and introverted components are the rule
- The little connectivity that exists is via long
paths - Practitioners stop communicate to relevant theory
interaction unpleasant, unfriendly, defensive
style The field is in crisis.
56- Revolution as in natural science
- Practitioners (having given up on theory) develop
and use their own abstractions, models, and
mathematical techniques - while theoreticians make their own attempts to
reconnect to practice (responding to pressures
from within their community and outside). - The uninspiring practical problems and the
unresponsive theoretical work that triggered the
crisis become less central, and new small
research traditions blossom. - Well-targeted exploratory theory connects several
of them, and a new healthy state emerges from the
ashes. A successfully championed new research
paradigm may then take over
57Why this relational model is applied in computer
science
- (1) It was a powerful and attractive proposal
(whose plausibility was expertly supported by
theoretical arguments) - (2) it was explicitly open-ended, a whole
framework for research problems, applications,
and experiments - (3) it came as the result of a crisis (or was it
immature science?) - (4) it was indeed followed by a period of normal
science. - we are now in the blues of a crisis, or even in
the flames of an on-going revolution
58A Brief History of Practice
- Ancient Greek tradition strongly favors theory
over practice (Aristotle) - Before the last century, an inventor could become
famous only if he was a moonlighting major
theoretician or artist (Archimedes, Aristarchus,
Leonardo da Vinci) or if his invention helped in
the spreading of theoretical knowledge
(Gutenberg). - Practice starts obtaining a measure of
respectability with Galileo (1564- 1642) (and
later under the influence of the British
empiricist philosophers) - However, only after James Watt (1736- 1819) did
sophisticated theoretical knowledge come to the
assistance of practice and invention, thus
launching the industrial age and the traditions
of applied science and engineering
59- Respect for practice is so universal today
- Theory and practice collaborated two centuries,
with theory dominating important domains in
applied science due to its academic prowess and
prestige - Serious and systematic ideological attack against
the value and necessity of theory in applied
science seems to be a novel and disturbing
phenomenon of the last decade or so. - Histrory of computer science, is a miniature of
the history of science - The strongest influence came from
mathematics(and less from electrical engineering
and physics),