CES – VCU November 2003 Geodatabases William Shuart Center for Environmental Studies Virginia Commonwealth University

CES – VCU November 2003 So how do we get there when we are here?So how do we get there when we are here? Coverages Shapefiles CAD Files INFO XLS Access Legacy DB

CES – VCU November 2003 GIS Data Counties Streams Collection data Biological Museum iMac Applications No integrated way to link client-tracking to billing or prospects to past projects

CES – VCU November 2003 Integration Examples: Once we integrate the GIS component we can begin to perform spatial analysis. Where are my top-billing clients? What areas in my territory are underserved? Traveling salesman analyses iMac GIS Data Counties Streams Collection data Biological Museum

CES – VCU November 2003 Feature class Table that also stores shapes for featuresTable that also stores shapes for features All features in a feature class have the same:All features in a feature class have the same: –Geometry –Attribute fields –Spatial reference Coordinate systemCoordinate system –Behavior

CES – VCU November 2003 Feature datasets Contain feature classesContain feature classes –All share the same spatial reference –Never tables and geometry Required for geometric networksRequired for geometric networks –Manage network connectivity Required for topologiesRequired for topologies –Spatial relationship between feature classes

CES – VCU November 2003 Databases Attribute data in many ways is tied to spatial locationAttribute data in many ways is tied to spatial location Traditional databases, e.g. Access can not store a ‘point’ as a field type.Traditional databases, e.g. Access can not store a ‘point’ as a field type. Most spatial data formats (Coverage, shapefile) can not be used inside a relational databaseMost spatial data formats (Coverage, shapefile) can not be used inside a relational database Beneficial to store biological data along with spatial data inside a database.Beneficial to store biological data along with spatial data inside a database.

CES – VCU November 2003 Geodatabase A container for spatial and attribute dataA container for spatial and attribute data –GIS data stored in a relational database –Scaleable solutions (personal and enterprise database) –Supports data integrity with rules Tools to migrate existing GIS dataTools to migrate existing GIS data

CES – VCU November 2003 Looking inside the Geodatabase Feature dataset Feature classes, subtypes PolygonRoute LineDimension Point Annotation Relationship class Geometric Networks spatial reference Topology Tables, subsets Raster Datasets Survey Datasets Locators AddressesRoute Events X,Y locationsRoute Locations Zip Codes Validation Rules Attribute Defaults Connectivity Rules Attribute Domains Relationship Rules Split/Merge Policies Topology Rules

CES – VCU November 2003 Advantages of the Geodatabase An RDBMS for spatial and attribute dataAn RDBMS for spatial and attribute data Other advantagesOther advantages Enhanced Topology Topology Rules Attribute Validation (domain and null value) Scaleable Storage Solutions Relationships (referential integrity) Object subtypes (support rules) Custom Features Multi-user editing (SDE)

CES – VCU November 2003 Personal geodatabase Multiuser geodatabase Storing the geodatabase Personal geodatabasePersonal geodatabase –Microsoft Access –Provided out-of-the-box ArcSDE geodatabaseArcSDE geodatabase –Enterprise RDBMS –Need ArcSDE License The differencesThe differences –Data volume and speed –Multiuser with ArcSDE only –Raster with ArcSDE only Use ArcCatalog to manage bothUse ArcCatalog to manage both ArcGIS ArcSDE No connect ArcSDE connect Direct connect

CES – VCU November 2003 Geodatabase tables Collections of rows and columnsCollections of rows and columns –Non-spatial May have behaviorMay have behavior –Subtypes –Default values –Domains May participate in relationshipsMay participate in relationships Origin table (look up table) Destination table (feature class)

CES – VCU November 2003 Subtypes Groups of objects within a feature class or tableGroups of objects within a feature class or table –Assign different rules to each subtype Attribute domains, topology rules, network rules, etc.Attribute domains, topology rules, network rules, etc. –Grouped by an integer attribute

CES – VCU November 2003 Domains Rules for attributesRules for attributes –Range Well depth range : feetWell depth range : feet –Coded Values Type: Bored or ArtesianType: Bored or Artesian Property of the geodatabaseProperty of the geodatabase –Can apply a domain for many fields –Apply to all records or by subtype Create them in ArcCatalog, use them in ArcMapCreate them in ArcCatalog, use them in ArcMap –Prevents errors, can label features, find errors

CES – VCU November 2003 Relationship classes Links objects in origin and destination tableLinks objects in origin and destination table –Key fields establish relationship Provides:Provides: –Read/write access –Referential integrity –Relationship rules –Support for versioning Origin table (look up table) Destination table (feature class)

CES – VCU November 2003 Rasters in the geodatabase Images and gridsImages and grids –Image formats: TIFF, BMP, SID, etc. –Grids (Native ESRI raster) ArcSDE geodatabases stores asArcSDE geodatabases stores as –Separate rasters May mosaic during loadingMay mosaic during loading –Raster catalogs Internal or referenced to file- based dataInternal or referenced to file- based data Not available in the personal geodatabase

CES – VCU November 2003 Geodatabase rules Attribute defaultsAttribute defaults Attribute domainsAttribute domains –Legal values –Split/merge policies Connectivity rulesConnectivity rules Relationship rulesRelationship rules Topology rulesTopology rules

CES – VCU November 2003 Data Loading Import / Export with ArcCatalog or ArcToolboxImport / Export with ArcCatalog or ArcToolbox –Creates a new feature class –Fast and easy but less control Export with ArcMapExport with ArcMap –Creates a new class –Can export selected features Load data with ArcCatalogLoad data with ArcCatalog –Simple data loader Into an existing class, or emptyInto an existing class, or empty No networks or topology allowedNo networks or topology allowed Load data with ArcMapLoad data with ArcMap –Object Loader Into an existing classInto an existing class Networks and topology allowedNetworks and topology allowed

CES – VCU November 2003 Create your own Use ArcCatalogUse ArcCatalog –Step 1: right-click –Step 2: new –Step 3: Select User input:User input: –Name –Relationships –Field names –Spatial reference

CES – VCU November 2003 ArcSDE Database Use ArcCatalogUse ArcCatalog

CES – VCU November 2003 Customization Application customizationApplication customization –VBA code –Catch interesting editor events (OnNew, OnChanged, –Code will be included in the *.mxd Database customizationDatabase customization –Custom class extensions –Custom object (VB, C++)

CES – VCU November 2003 Existing data models Data models are schema templatesData models are schema templates Many typesMany types –Provides UML models and personal geodatabases Saves development timeSaves development time Modify template to serve your needsModify template to serve your needs Test, update, test, updateTest, update, test, update

CES – VCU November 2003