Transcript www.spatial.cs.umn.edu

Databases in the Cloud:
Elysian Field or Briar Patch?
www.drdobbs.com,
August 2009
Group 20
Resource Description Framework
Data stored in triples



subject = resource
predicate = traits and relation
of subject to object
object = the value
-Uses multi-graph that often
better expresses info than
relational model
-Example predicates:
1. who is a 2. whose name is
3. whose email is 4.whose title is
SQL/XML Databases
Why XML

Widely used to store and
share data on internet
SQL/XML platforms:
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Rich query model, suppoting:
SQL, XQuery, XPath, and
SPARQL queries
Query Optimizer generates
access path to data (Does
not rely on application logic)
Public vs Private Clouds
Public
Pros
Private
Pros

less expensive


more flexibility

Cons

security concerns

more limited uptime

greater security and reliability
better utilizes existing
infrastructure
custom designed for business
needs
Cons

more expensive

concern about multiple APIs
Concerns with Clouds
-Diversity of APIs
–
Some platforms
support familiar APIs
(ODBC, JDBC,
ADO.NET)
-Security, multi-tenancy
–
Could be overcome
with encryption,
authorization, roles,
policy-based security
controls, etc
-Reliability
–
Public cloud does not
provide 99.99%
Wrap-up

Public Cloud security issues
mitigated




Salesforce.com
Some concerns partially
addressed with private or
hybrid clouds
Fault tolerance solutions offer
promise
Reliability problems are still
an issue

Amazon Xmas Eve
outage
References
http://www.drdobbs.com/database/databases-inthe-cloud-elysian-fields-or/218900502
http://www.accenture.com/SiteCollectionDocumen
ts/PDF/Accenture-New-Era-Banking-CloudComputing-Changes-Game.pdf
http://www.w3.org/RDF/advantages.html
http://gigaom.com/2012/12/31/amazon-blames-