Transcript Database Architectures and Implementations

Database Architectures
and Implementations
We shape our buildings:
thereafter they shape us
Winston Churchill
Database Architectures and
Implementations
An architecture should
Respond to queries in a timely manner
Minimize the cost of processing data
Minimize the cost of storing data
Minimize the cost of data delivery
These objectives can be conflicting
No-schema architecture
One-schema architecture
Two-schema architecture
ANSI SPARC
A 1972 committee to examine standardization of database technology
Focused on the interfaces
Internal
Conceptual
External
External
The clients’ views of the system
There can be multiple views
Conceptual
The database designer’s view
The data model
Includes all files and all fields within files
Should be unconstrained by consideration of
storage structures and data access
mechanisms
Can include security and integrity
considerations
Internal
The lowest level
Considers data storage and access
Includes indexing and record
sequencing