1	Geodatabases and ArcGIS Geog 378 – Geographic Information Systems CCSU - Geography
2	Types of Geodatabases Personal File Enterprise/Organization/SDE
3	Types of Geodatabases Personal MS Access-based Creation “engine” comes with base GIS software Can be managed with Access as well as ArcCatalog 2 gigabyte limit Not good for large rasters, e.g. air photos Good for small to medium number of readers One editor and not while others are reading
4	Types of Geodatabases, cont. File Geodatabase Collection of files in a folder Hold up to a terrabyte of data Compressible Cannot be edited compressed Supports small to medium amounts of users Can be edited (one editor) during reads New with 9.2 Plans to phase out personal geodatabases
5	Types of Geodatabases, cont. Organization/Enterprise/SDE Database Requires installation of underlying RDBMS Oracle, SQL Server, DB2, Informix Spatial data stored directly in the database Does not come with base software (Sql Express does) Additional purchase of Spatial Database Engine Middleware that manages indexing and communications (TCP/IP) Unlimited size and number of users Supports multiple simultaneous editing Versions\ Highest data security
6	Common Advantages Organization Containers Feature datasets Geodatabase Topology Rules applied to spatial data, e.g. polygons must not overlap, lines must touch other lines Spatial validation during database construction Domains – attribute validation
7	E/O/SDE Database Advantages Must have for… Large number of concurrent users Multiple editors Significant improvement on security Users log into database Password protected Owners of data decide who can do what with the data, e.g. view, select, edit