9/27/2012
SC0206: Database Systems 01. Introduction To Database Systems
SCO206: Database Systems SCO206: Database Systems
. 1 .
Definition: Database Examples of traditional database applications
• A collection of related data • Banking systems – manage deposits,
• Represents some part of the real world withdrawals, loan issuance and repayment
(miniworld). Changes in miniworld reflected in etc.
database • Hotel/Airline Reservation systems
• Collection of data is logically coherent (with some • A computerized library catalog
inherent meaning)
• Point of Sale System
• Designed, built and populated for a specific
purpose – for an intended group of users and • E‐Commerce storefront system
some application in which the users are interested
SCO206: Database Systems
• Largely Numeric and Textual Databases
SCO206: Database Systems
3 4
Other Basic Definitions
Recent Advances In Database Applications
• Multimedia Databases: • Data:
– Store pictures, video clips, sound messages etc. – Known facts that can be recorded and have an implicit
meaning e.g. names, addresses, telephone etc. about
• Geographic Information Systems (GIS): clients
– Store and analyze maps, weather data, satellite images
• Database Management System (DBMS):
• Data Warehouses:
– A software package/ system to facilitate the creation and
– Used to extract and analyze info from very large DBs for
decision making maintenance of a computerized database.
• Real‐time and Active Databases: • Database System:
– Such as are used in controlling industrial and – The DBMS software together with the data itself.
manufacturing processes (Sometimes the definition includes applications that
manipulate the database)
• WWW databases
SCO206: Database Systems SCO206: Database Systems
5 6
1
, 9/27/2012
Simplified Database System Environment Important DBMS Functionality
• Defining a database:
– Specifying data types, structures and constraints
• Constructing a database:
– Store data on some medium controlled by DBMS
• Manipulating the database:
– Retrieval: Querying, generating reports
– Modification: Insertions, deletions and updates to its content
– Accessing the database through applications
• Sharing:
– Allow concurrent access to multiple users and programs – yet ,
keeping all data valid and consistent
SCO206: Database Systems SCO206: Database Systems
7 8
Other Important Functions Example of a Database
• Protection • Mini‐world for the example: Part of a UNIVERSITY
– System protection against hardware or software environment.
malfunction
• Some mini‐world entities:
– Security Protection: against unauthorized access
– STUDENTs
• Maintaining
M i t i i The
Th Database
D t b System
S t – COURSEs
– Maintaining the database and associated programs over – SCHEDULEs (of COURSEs)
the lifetime of the database application … as
– (academic) DEPARTMENTs
requirements evolve over time
• Called database, software, and system maintenance – INSTRUCTORs
• Presentation and Visualization of data
SCO206: Database Systems SCO206: Database Systems
9 10
Example of a Database Sample Database of Students, Courses
• Some mini‐world relationships:
– SCHEDULEs are of specific COURSEs
– STUDENTs take SCHEDULEs
– COURSEs have prerequisite COURSEs
– INSTRUCTORs teach SCHEDULEs
– COURSEs are offered by DEPARTMENTs
– STUDENTs major in DEPARTMENTs
Note: The above could be expressed in the ENTITY‐
RELATIONSHIP data model.
SCO206: Database Systems SCO206: Database Systems
11 12
2
SC0206: Database Systems 01. Introduction To Database Systems
SCO206: Database Systems SCO206: Database Systems
. 1 .
Definition: Database Examples of traditional database applications
• A collection of related data • Banking systems – manage deposits,
• Represents some part of the real world withdrawals, loan issuance and repayment
(miniworld). Changes in miniworld reflected in etc.
database • Hotel/Airline Reservation systems
• Collection of data is logically coherent (with some • A computerized library catalog
inherent meaning)
• Point of Sale System
• Designed, built and populated for a specific
purpose – for an intended group of users and • E‐Commerce storefront system
some application in which the users are interested
SCO206: Database Systems
• Largely Numeric and Textual Databases
SCO206: Database Systems
3 4
Other Basic Definitions
Recent Advances In Database Applications
• Multimedia Databases: • Data:
– Store pictures, video clips, sound messages etc. – Known facts that can be recorded and have an implicit
meaning e.g. names, addresses, telephone etc. about
• Geographic Information Systems (GIS): clients
– Store and analyze maps, weather data, satellite images
• Database Management System (DBMS):
• Data Warehouses:
– A software package/ system to facilitate the creation and
– Used to extract and analyze info from very large DBs for
decision making maintenance of a computerized database.
• Real‐time and Active Databases: • Database System:
– Such as are used in controlling industrial and – The DBMS software together with the data itself.
manufacturing processes (Sometimes the definition includes applications that
manipulate the database)
• WWW databases
SCO206: Database Systems SCO206: Database Systems
5 6
1
, 9/27/2012
Simplified Database System Environment Important DBMS Functionality
• Defining a database:
– Specifying data types, structures and constraints
• Constructing a database:
– Store data on some medium controlled by DBMS
• Manipulating the database:
– Retrieval: Querying, generating reports
– Modification: Insertions, deletions and updates to its content
– Accessing the database through applications
• Sharing:
– Allow concurrent access to multiple users and programs – yet ,
keeping all data valid and consistent
SCO206: Database Systems SCO206: Database Systems
7 8
Other Important Functions Example of a Database
• Protection • Mini‐world for the example: Part of a UNIVERSITY
– System protection against hardware or software environment.
malfunction
• Some mini‐world entities:
– Security Protection: against unauthorized access
– STUDENTs
• Maintaining
M i t i i The
Th Database
D t b System
S t – COURSEs
– Maintaining the database and associated programs over – SCHEDULEs (of COURSEs)
the lifetime of the database application … as
– (academic) DEPARTMENTs
requirements evolve over time
• Called database, software, and system maintenance – INSTRUCTORs
• Presentation and Visualization of data
SCO206: Database Systems SCO206: Database Systems
9 10
Example of a Database Sample Database of Students, Courses
• Some mini‐world relationships:
– SCHEDULEs are of specific COURSEs
– STUDENTs take SCHEDULEs
– COURSEs have prerequisite COURSEs
– INSTRUCTORs teach SCHEDULEs
– COURSEs are offered by DEPARTMENTs
– STUDENTs major in DEPARTMENTs
Note: The above could be expressed in the ENTITY‐
RELATIONSHIP data model.
SCO206: Database Systems SCO206: Database Systems
11 12
2