1. GI Science Database Management Systems Nigel Trodd Coventry University

2. GIS are INFORMATION systems  what is the role of databases?  what do they do?  how do they do it ?

3. Spatial data modelling

4. databases...... a body of related data stored in a structured manner

5. a body of unstructured dataa body of structured data

7. store & retrieve data efficiently

8. and …  check  integrate  manipulate a D ata B ase M anagement S ystem

10. a DBMS is 'a software system with capabilities to define data and their attributes, establish relationships among data items, manipulate the data and manage the data' Stamper & Price (1990)

11. but

12. Spatial data are different Putting the G into an IS

13. how do databases store spatial data ? Spatial data = attribute + geometry / topology

15. but things are rarely simple

16. rdbms e.g.  dBase  MS Access  Oracle 9i Codd’s laws

17. Storing spatial data: relational db

19. geodb

20. Summary  data, databases, dbms, geodb  database models –flat file, O-O –relational dbms  tables (tuples) –linked by unique identifiers  efficient storage, effective retrieval