Features, Formats & Attributes GIS 458 Spring 2006.

Features, Formats & Features, Formats & AttributesAttributes

GIS 458GIS 458

Spring 2006Spring 2006

Layer TypesLayer Types

VectorVector RasterRaster Terrain and Other SurfacesTerrain and Other Surfaces OtherOther

• AddressesAddresses• Geoprocessing ModelsGeoprocessing Models• Survey DataSurvey Data• NetworksNetworks

Vector DataVector Data

Discrete DataDiscrete Data Have precise shape and positionHave precise shape and position Best for defined shapes and Best for defined shapes and

boundariesboundaries Have attributes and behaviorHave attributes and behavior PointsPoints

• Zero-DimensionalZero-Dimensional• Features too small to be lines or areasFeatures too small to be lines or areas• Stored as single x,y coordinatesStored as single x,y coordinates

Vector DataVector Data LinesLines

• One-DimensionalOne-Dimensional• Features too narrow to be areasFeatures too narrow to be areas• Stored as series of ordered x,y coordinatesStored as series of ordered x,y coordinates• Segments:Segments:

StraightStraight CircularCircular EllipticalElliptical SplinedSplined

PolygonsPolygons• Two-DimensionalTwo-Dimensional• Features that cover a broad geographic areaFeatures that cover a broad geographic area• Stored as series of segments that enclose an areaStored as series of segments that enclose an area

AnnotationAnnotation• Descriptive labelsDescriptive labels• Associated with featuresAssociated with features• Display names and attributesDisplay names and attributes

Raster DataRaster Data

Gridded data composed of cells or pixels Gridded data composed of cells or pixels (picture elements)(picture elements)

Two-DimensionalTwo-Dimensional Values can depict various dataValues can depict various data

• Light values (spectral)Light values (spectral)• Elevation (thematic)Elevation (thematic)• Density (thematic)Density (thematic)

Discrete or ContinuousDiscrete or Continuous Can also be stored in an attribute fieldCan also be stored in an attribute field

• Photo of a buildingPhoto of a building

Terrain & Other SurfacesTerrain & Other Surfaces

Triangulated Irregular Network (TIN)Triangulated Irregular Network (TIN) Model of a surfaceModel of a surface Stored as:Stored as:

• Integrated nodesIntegrated nodes• Triangles with edgesTriangles with edges

Enable surface analysisEnable surface analysis Cannot be stored directly in Cannot be stored directly in

geodatabasegeodatabase

Other Layer TypesOther Layer Types

AddressesAddresses• Data stored in databaseData stored in database• ““Locators” create features for locationsLocators” create features for locations

Geoprocessing ModelsGeoprocessing Models• You create tools and store themYou create tools and store them

Survey DataSurvey Data• Data tables tied to feature coordinatesData tables tied to feature coordinates

NetworksNetworks• Require connectivity & topologyRequire connectivity & topology

AttributesAttributes

Quality of an objectQuality of an object• SizeSize• DensityDensity• NameName• FlowFlow• DateDate• PopulationPopulation

A feature can have a number of attributesA feature can have a number of attributes Allow analysis & symbolizationAllow analysis & symbolization

GIS 458GIS 458


Instructor: Larry ClampInstructor: Larry Clamp

Course TopicsCourse Topics Design ProcessDesign Process Layer Design & FormatsLayer Design & Formats

• Raster vs. VectorRaster vs. Vector• Point, Line or Polygon?Point, Line or Polygon?

RelationshipsRelationships• SpatialSpatial• Non-SpatialNon-Spatial

Attribute Table DesignAttribute Table Design• Defining Appropriate FieldsDefining Appropriate Fields• Assigning Appropriate Field TypesAssigning Appropriate Field Types

Text, Integer, Double…Text, Integer, Double…

Course Topics, continuedCourse Topics, continued

Database FundamentalsDatabase Fundamentals• PurposePurpose• Personal vs. EnterprisePersonal vs. Enterprise

Database DesignDatabase Design Database ImplementationDatabase Implementation

Course Topics, continuedCourse Topics, continued

Software SelectionSoftware Selection• Database software (Oracle, SQL, etc.)Database software (Oracle, SQL, etc.)• GIS Software…GIS Software…isis ESRI the best? ESRI the best?

Data StandardsData Standards• FGDCFGDC

PersonnelPersonnel Project ManagementProject Management Data MiningData Mining

BREAK!!!!BREAK!!!!

GIS (Geographic Information GIS (Geographic Information System) System)

Consists of:Consists of:• Computer hardwareComputer hardware• SoftwareSoftware• Geographic dataGeographic data• PersonnelPersonnel

Is a computer system that stores and links Is a computer system that stores and links geographically-referenced information with geographically-referenced information with graphic map features to allow a wide range of:graphic map features to allow a wide range of:• Information processing and retrievalInformation processing and retrieval• Display operationsDisplay operations• Map productionMap production• Analysis, andAnalysis, and• ModelingModeling

Benefits of a GIS (Functionality)Benefits of a GIS (Functionality)

Data entry/updating: access the database to Data entry/updating: access the database to update, add or delete informationupdate, add or delete information

Data conversion: take diverse information, Data conversion: take diverse information, formats, etc. and make them compatibleformats, etc. and make them compatible

Data retrieval: take massive amounts of stored Data retrieval: take massive amounts of stored information and access it information and access it

Data manipulation: select via query and classify Data manipulation: select via query and classify (symbolize) in different manners(symbolize) in different manners

Data presentation: present retrieved information Data presentation: present retrieved information in either text, tabular or map format.in either text, tabular or map format.

Spatial analysis: take spatial data and make Spatial analysis: take spatial data and make queries (from simple to complex) and generate queries (from simple to complex) and generate new data from the original setnew data from the original set

Three general operations in a GIS:Three general operations in a GIS:

1. Attribute queries (aspatial queries):1. Attribute queries (aspatial queries):• How many parcels in an attribute table are zoned How many parcels in an attribute table are zoned

R-7 and what is their total acreage?R-7 and what is their total acreage? 2. Spatial queries: 2. Spatial queries:

• How many pulp plants are located within 500 How many pulp plants are located within 500 meters of a river?meters of a river?

3. Generation of new data sets from the 3. Generation of new data sets from the original database:original database:• Out of a marine mammal dataset, where are just Out of a marine mammal dataset, where are just

the Beluga whales located?the Beluga whales located?• Are there areas where ring seals and orcas Are there areas where ring seals and orcas

overlap? overlap?

What is “Spatial Data”?What is “Spatial Data”?

Spatial means it is “mappable”, that is, Spatial means it is “mappable”, that is, every piece of information is attached to a every piece of information is attached to a specific object on the map and that specific object on the map and that object’s location on the map is object’s location on the map is geographically-referencedgeographically-referenced

Reference systems typically use Reference systems typically use latitude/longitude, UTM, SPC or some type latitude/longitude, UTM, SPC or some type of x,y coordinate systemof x,y coordinate system

Where do we get “Spatial Data”?Where do we get “Spatial Data”?

From a variety of sources:From a variety of sources:• U.S. censusU.S. census• Land use surveysLand use surveys• Satellite imagerySatellite imagery• Aerial photographsAerial photographs• Paper mapsPaper maps

Problem: compatibilityProblem: compatibility• Projections/coordinate systems--Albers Equal-Projections/coordinate systems--Albers Equal-

Area Conic vs. UTMArea Conic vs. UTM• Map scale--1:2,000 vs. 1:2,000,000Map scale--1:2,000 vs. 1:2,000,000• Data formats--DRG, (raster), Shapefile (vector)Data formats--DRG, (raster), Shapefile (vector)

Examples of GIS Data Examples of GIS Data StructuresStructures

Organizing Geographic Organizing Geographic DataData

GIS 458GIS 458Spring 2006Spring 2006

Larry ClampLarry Clamp

Parts of the WholeParts of the Whole

GeodatabaseGeodatabase Geographic DatasetsGeographic Datasets Object ClassesObject Classes Feature ClassesFeature Classes Topological ClassesTopological Classes Relationship ClassesRelationship Classes

GeodatabaseGeodatabase

A collection of data typesA collection of data types• Datasets & feature, object and relationship Datasets & feature, object and relationship

classesclasses Can span one, several, or many Can span one, several, or many

geodatabasesgeodatabases Manage seamless geographic dataManage seamless geographic data Two main typesTwo main types

• PersonalPersonal Represent small to medium-sized datasetsRepresent small to medium-sized datasets

• EnterpriseEnterprise Represent large or complex datasets (multiple users)Represent large or complex datasets (multiple users)

Geographic DatasetsGeographic Datasets

Feature DatasetFeature Dataset• Collection of feature classesCollection of feature classes• Common coordinate systemCommon coordinate system• FC’s must be in FD’s for topologyFC’s must be in FD’s for topology

Raster DatasetRaster Dataset• Simple (basic GRID)Simple (basic GRID)• Compound (multiple bands, etc.)Compound (multiple bands, etc.)

Triangulated (TIN) DatasetTriangulated (TIN) Dataset

Object ClassesObject Classes

Table that can associate behaviorTable that can associate behavior Descriptive information about objectsDescriptive information about objects

• OwnersOwners• Stream CodesStream Codes• AnnotationAnnotation

Feature ClassesFeature Classes

Collection of features with same Collection of features with same geometrygeometry• Points, lines, polygonsPoints, lines, polygons

Simple feature classesSimple feature classes• No topologyNo topology• Features are independent of one anotherFeatures are independent of one another

Topological feature classesTopological feature classes• Features are bound to one anotherFeatures are bound to one another• Share certain behaviorShare certain behavior

RelationshipsRelationships

No…SeriouslyNo…Seriously

Relationship classRelationship class• Table that stores realtionships between Table that stores realtionships between

features or objectsfeatures or objects• Models dependencies between objectsModels dependencies between objects• Can control what happens to related Can control what happens to related

objectsobjects RemovedRemoved ChangedChanged

Keep it Simple…Keep it Simple…

Geodatabase = Filing CabinetGeodatabase = Filing Cabinet

• Feature Dataset = Filing Cabinet DrawerFeature Dataset = Filing Cabinet Drawer

Feature Class = Individual Folder in DrawerFeature Class = Individual Folder in Drawer

Sub-Types & Attribute Sub-Types & Attribute DomainsDomains

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Sub-TypesSub-Types Objects (rows) in a table or feature class Objects (rows) in a table or feature class

grouped by an attributegrouped by an attribute• Roads by class: Highways, major roads, Roads by class: Highways, major roads,

arterials, etc.arterials, etc. Allow users to make validation rules more Allow users to make validation rules more

specific to dataspecific to data Help insure data qualityHelp insure data quality Speed up data entry and editingSpeed up data entry and editing Help eliminate need for additional classesHelp eliminate need for additional classes

• Wells: Different class for public, agricultural or Wells: Different class for public, agricultural or monitoring wells ormonitoring wells or

• Just different sub-types?Just different sub-types?

Sub-Types, continuedSub-Types, continued

Based on integer attribute fieldBased on integer attribute field Integer codes and descriptions Integer codes and descriptions

enteredentered Editor constrained to entered valuesEditor constrained to entered values In ArcMap, description is displayedIn ArcMap, description is displayed Description used for labelingDescription used for labeling

Setting Sub-TypesSetting Sub-Types

Set as properties of an existing table Set as properties of an existing table or feature classor feature class

Go to Properties dialogGo to Properties dialog Select integer sub-type fieldSelect integer sub-type field Input code and descriptionInput code and description Can also set defaults and domainsCan also set defaults and domains

Attribute DomainsAttribute Domains

Define legal field values for tables, feature Define legal field values for tables, feature classes, or sub-typesclasses, or sub-types

Defined as properties of the geodatabaseDefined as properties of the geodatabase Can be shared across the geodatabaseCan be shared across the geodatabase Assigned to fields by editing field Assigned to fields by editing field

properties of tables & feature classesproperties of tables & feature classes Do not constrain incorrect data entry but Do not constrain incorrect data entry but

will find errorswill find errors• Validation tool on Editor menuValidation tool on Editor menu

Legal ValuesLegal Values

Two Types of domainsTwo Types of domains• Range and Coded ValuesRange and Coded Values

Type used depends on nature of Type used depends on nature of attribute dataattribute data

Range vs. Coded ValuesRange vs. Coded Values

Range domainsRange domains• Apply to values for numeric attributesApply to values for numeric attributes• Used for measured dataUsed for measured data

Well depthWell depth Contamination levelsContamination levels Power pole heightsPower pole heights

• Legal minimum and maximumLegal minimum and maximum

Range vs. Coded ValuesRange vs. Coded Values

Coded valuesCoded values• Apply to any type of attributeApply to any type of attribute

Text, numeric, date, etc.Text, numeric, date, etc.

• Used for coded dataUsed for coded data Land-use codesLand-use codes Water pipe material codesWater pipe material codes Street surfacing codesStreet surfacing codes

• Define list of legal codes and their Define list of legal codes and their descriptionsdescriptions

Splitting & Merging FeaturesSplitting & Merging Features

Domains allow you to define how Domains allow you to define how attributes are handled during attributes are handled during splitting & mergingsplitting & merging

Split policySplit policy Merge policyMerge policy

Split PoliciesSplit Policies

Defines what values are assigned to Defines what values are assigned to resulting featuresresulting features• Default valueDefault value

Each take on a default value you setEach take on a default value you set

• Duplicate valueDuplicate value Each take on a copy of original valueEach take on a copy of original value

• Geometry ratioGeometry ratio Each take on a ratio of the original valueEach take on a ratio of the original value

Merge PoliciesMerge Policies

Dictates what happens to values of Dictates what happens to values of merged featuresmerged features• Default valueDefault value

Each take on a default value you setEach take on a default value you set Only policy that applies to nonnumeric fields Only policy that applies to nonnumeric fields

and coded value domainsand coded value domains

• SumSum Sum of the original featuresSum of the original features

• Geometry weightedGeometry weighted Weighted average of original featuresWeighted average of original features

SummarySummary

Field TypesField Types Domain TypeDomain Type Split PoliciesSplit Policies Merge PoliciesMerge Policies

Double, Float, Double, Float, Long Integer, Long Integer, Short Integer, Short Integer, Date, TextDate, Text

Coded ValueCoded Value Default value, Default value, DuplicateDuplicate Default valueDefault value

Double, Float, Double, Float, Long Integer, Long Integer, Short Integer, Short Integer, DateDate

RangeRangeDefault value, Default value, Duplicate, Duplicate, Geometry ratioGeometry ratio

Default value, Default value, Sum, Sum,

Weighted Weighted averageaverage

Table Design & Table Design & Importing DataImporting Data

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Ways to create tablesWays to create tables

ArcCatalogArcCatalog• Right click locationRight click location

Folder, geodatabase…Folder, geodatabase…

• Select New>Table to access wizardSelect New>Table to access wizard• You can import fields from other tablesYou can import fields from other tables

Geoprocessing (ArcToolbox)Geoprocessing (ArcToolbox)• Under Data Management ToolsUnder Data Management Tools• Select Table toolset > Create TableSelect Table toolset > Create Table

Table Field PropertiesTable Field Properties AliasAlias Allow NULL ValuesAllow NULL Values Default ValueDefault Value DomainDomain OBJECTIDOBJECTID LengthLength PrecisionPrecision ScaleScale BLOBBLOB RasterRaster

AliasAlias

Alternate field name for display in Alternate field name for display in ArcMapArcMap

Less cryptic…Less cryptic… Can be changed after the table is Can be changed after the table is

createdcreated

Allow NULL ValuesAllow NULL Values

Indicates field may or may not Indicates field may or may not contain null datacontain null data

Null value = absence of recorded Null value = absence of recorded valuevalue

Different than 0 (which is a value)Different than 0 (which is a value) May NOT be changed after table is May NOT be changed after table is

created created

Default ValueDefault Value

Value that is automatically assigned Value that is automatically assigned for a new recordfor a new record

May be changed after table is May be changed after table is createdcreated

DomainDomain

Assigned geodatabase domain for Assigned geodatabase domain for fieldfield

Defines legal valuesDefines legal values Can also define how feature Can also define how feature

attributes are handled if they are attributes are handled if they are merged or splitmerged or split

May be changed after table is May be changed after table is createdcreated

OBJECTIDOBJECTID

Automatically generatedAutomatically generated DO NOT delete or change it in any DO NOT delete or change it in any

way!!way!!

LengthLength

Maximum number of characters to Maximum number of characters to store in text fieldstore in text field

Set as an integerSet as an integer

PrecisionPrecision

Maximum number of digits for a Maximum number of digits for a numeric fieldnumeric field


ScaleScale

Maximum number of decimal digits Maximum number of decimal digits for a decimal numeric fieldfor a decimal numeric field


BLOBBLOB

Binary large objectBinary large object Data stored in the geodatabase as a Data stored in the geodatabase as a

long sequence of binary numberslong sequence of binary numbers Stores images, multimedia, or bits of Stores images, multimedia, or bits of

codecode ArcGIS doesn’t provide end-user toolsArcGIS doesn’t provide end-user tools Must write custom objects or Must write custom objects or

applications to manage a BLOB fieldapplications to manage a BLOB field

RasterRaster

New attribute typeNew attribute type Stores raster within or alongside the Stores raster within or alongside the

geodatabasegeodatabase ArcGIS views many file formats but outputs ArcGIS views many file formats but outputs

as a GRID, IMAGINE, or TIFFas a GRID, IMAGINE, or TIFF Will convert for youWill convert for you Only one raster field allowed in a table or Only one raster field allowed in a table or

feature classfeature class Use a different table with a relate to Use a different table with a relate to

associate moreassociate more

Naming ConventionsNaming Conventions

Table name, feature class and field Table name, feature class and field names must be compatible with names must be compatible with underlying RDBMSunderlying RDBMS

For ESRI this means:For ESRI this means:• No spacesNo spaces• Use underscores or run words togetherUse underscores or run words together• Field names limited to ten charactersField names limited to ten characters

Use an alias for more descriptive nameUse an alias for more descriptive name

Field Data TypesField Data TypesData TypeData Type BytesBytes RangeRange ApplicationApplication

Short IntegerShort Integer 22 -32,768 to 32,767-32,768 to 32,767 Numbers without fractions Numbers without fractions within specific ranges; coded within specific ranges; coded valuesvalues

Long IntegerLong Integer 44 -2,147,483,648 to -2,147,483,648 to 2,147,483,6472,147,483,647

Numbers without fractions Numbers without fractions within specific rangewithin specific range

FloatFloat 44 Approx. -3.4EApprox. -3.4E-38-38 to 1.2E to 1.2E3838 Numbers with fractions within Numbers with fractions within specific rangespecific range

DoubleDouble 88 Approx. -2.2EApprox. -2.2E-308-308 to 1.8E to 1.8E308308 Numbers with fractions within Numbers with fractions within specific rangespecific range

TextText VariesVaries Up to 64,000 charactersUp to 64,000 characters Names or other textual Names or other textual qualitiesqualities

DateDate 88 Mm/dd/yyy, hh:mm:ss; Mm/dd/yyy, hh:mm:ss; AMP/PMAMP/PM

Date and/or timeDate and/or time

BLOBBLOB VariesVaries VariesVaries Images or other multimediaImages or other multimedia

RasterRaster VariesVaries Stores ImagesStores Images Storing imagesStoring images

Importing Data (vector data)Importing Data (vector data)

IMPORT toolsIMPORT tools• ArcCatalog context menu orArcCatalog context menu or• Geoprocessing toolsGeoprocessing tools

Simple Data Loader (ArcCatalog)Simple Data Loader (ArcCatalog)• Loads to existing table or feature classLoads to existing table or feature class

Empty or with data)Empty or with data) ArcMap Object LoaderArcMap Object Loader

• Loads to existing table or feature classLoads to existing table or feature class Empty or with data)Empty or with data)

Work for both personal or enterprise GDBWork for both personal or enterprise GDB

IMPORT toolsIMPORT tools

ArcCatalog menusArcCatalog menus• Right click on location to import…Right click on location to import…

Geoprocessing toolsGeoprocessing tools• ArcToolbox > Conversion Tools > To ArcToolbox > Conversion Tools > To

GeodatabasaeGeodatabasae Both use same toolsBoth use same tools

Simple Data LoaderSimple Data Loader

ArcCatalog context menus wizardArcCatalog context menus wizard Loads data into an existing table or Loads data into an existing table or

feature classfeature class• Object may be empty or contain dataObject may be empty or contain data• Data sources must have same schema Data sources must have same schema

(multiple)(multiple)• Feature classesFeature classes

Target and source MUST have same geometryTarget and source MUST have same geometry

• Can query to import only selected dataCan query to import only selected data• Geometric networks & versions not Geometric networks & versions not

supportedsupported

Object LoaderObject Loader

Accessible only in ArcMap edit sessionAccessible only in ArcMap edit session Must add as a custom toolMust add as a custom tool

• Tools>Customize>Commands>Data ConvertersTools>Customize>Commands>Data Converters Loads “complex data” to table or feature classLoads “complex data” to table or feature class

• Supports behavior as it loadsSupports behavior as it loads• Object may be empty or contain dataObject may be empty or contain data• Data sources must have same schema (multiple)Data sources must have same schema (multiple)• Feature classesFeature classes

Target and source MUST have same geometryTarget and source MUST have same geometry

• Can query to import only selected dataCan query to import only selected data

The Geodatabase The Geodatabase Design ProcessDesign Process

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Why is Good Design Why is Good Design Necessary?Necessary?

Questions to Answer:Questions to Answer:

• How can we employ GIS technology to:How can we employ GIS technology to: Improve existing functions?Improve existing functions?

Change goal achievement?Change goal achievement?

• What data is most beneficial?What data is most beneficial?

• What data can be acquired & stored?What data can be acquired & stored?

• Who will maintain the database?Who will maintain the database?

Establish Process to:Establish Process to:• Define goalsDefine goals• Identify, analyze and evaluate alternativesIdentify, analyze and evaluate alternatives• Agree on implementation planAgree on implementation plan

Design ObjectivesDesign Objectives

Avoid risks of lack of designAvoid risks of lack of design Satisfy objectives and requirementsSatisfy objectives and requirements Obtain necessary dataObtain necessary data Avoid unnecessary redundancyAvoid unnecessary redundancy Organize data for different usersOrganize data for different users Accommodate different data viewsAccommodate different data views Divide maintenance and usersDivide maintenance and users Appropriate feature representation, Appropriate feature representation,

organization & codingorganization & coding

Benefits of DesignBenefits of Design

Time consuming…but worth it!Time consuming…but worth it! Increased data retrieval & analysis Increased data retrieval & analysis

flexibilityflexibility Increased user application Increased user application

developmentdevelopment Better cost distributionBetter cost distribution More users supportedMore users supported Support for future developmentSupport for future development Less data redundancyLess data redundancy

Design GuidelinesDesign Guidelines

Involve UsersInvolve Users One Step at a TimeOne Step at a Time Build a TeamBuild a Team Be CreativeBe Creative Create Deliverables & MilestonesCreate Deliverables & Milestones Keep Goals and Objectives in FocusKeep Goals and Objectives in Focus Don’t Add Detail Too SoonDon’t Add Detail Too Soon Document Carefully!!!!!!Document Carefully!!!!!! Be FlexibleBe Flexible Use Model to PlanUse Model to Plan

Design StepsDesign Steps

Model the User’s ViewModel the User’s View Define Entities (features & objects) Define Entities (features & objects)

and Relationshipsand Relationships Identify Proper Entity (features & Identify Proper Entity (features &

objects) Representationobjects) Representation Match These to the Geodatabase Match These to the Geodatabase

ModelModel Organize into Geographic DatasetsOrganize into Geographic Datasets

Model the User’s ViewModel the User’s View

Ensure common understanding between Ensure common understanding between designers and usersdesigners and users

Identify Organizational FunctionsIdentify Organizational Functions• Business or service functions & processes Business or service functions & processes

are more stable than business organizationare more stable than business organization• What do they do?What do they do?

Identify Data RequirementsIdentify Data Requirements• Interact!Interact!• Who uses it and what is the nature of Who uses it and what is the nature of

interaction?interaction? Organize Data into Logical GroupingsOrganize Data into Logical Groupings Develop an Initial Implementation Plan Develop an Initial Implementation Plan

Define Entities and Define Entities and RelationshipsRelationships

Broad to NarrowBroad to Narrow Identify & Describe EntitiesIdentify & Describe Entities

• Use detailUse detail• Involve end users!Involve end users!

Identify & Describe RelationshipsIdentify & Describe Relationships• Use descriptive & interpreting statementsUse descriptive & interpreting statements

Use Diagrams to Show E & RUse Diagrams to Show E & R• Unified Modeling LanguageUnified Modeling Language

Identify Proper Entity Identify Proper Entity RepresentationRepresentation

Classify by Type of RepresentationClassify by Type of Representation Will it be used on a map?Will it be used on a map? Is shape significant for analysis?Is shape significant for analysis? Can it be accessed and visualized through Can it be accessed and visualized through

relationship to another feature?relationship to another feature? Will it have different representations at Will it have different representations at

different scales?different scales? Does it need annotation?Does it need annotation? Should it be a:Should it be a:

• Point, line or polygonPoint, line or polygon• A surface, raster, image, photo or drawingA surface, raster, image, photo or drawing• An objectAn object

No point, line or polygon requiredNo point, line or polygon required No geometric or graphic representationNo geometric or graphic representation

Match to the Geodatabase Match to the Geodatabase ModelModel

Determine Geodatabase RepresentationDetermine Geodatabase Representation Simple FeaturesSimple Features

• DiscreteDiscrete• No TopologyNo Topology

Complex FeaturesComplex Features• DiscreteDiscrete• Topology or participation in a networkTopology or participation in a network

PointsPoints LinesLines PolygonsPolygons ImagesImages SurfacesSurfaces ObjectObject

Organize into Geographic Organize into Geographic Datasets Datasets

Identify & Name DatasetsIdentify & Name Datasets Group Feature ClassesGroup Feature Classes

• Large feature classLarge feature class• SubtypesSubtypes

Custom behaviorCustom behavior Substantially different attributesSubstantially different attributes Different access requirementsDifferent access requirements

Define Topology NeedsDefine Topology Needs• Feature classes participating in topology or Feature classes participating in topology or

network must be in the same feature datasetnetwork must be in the same feature dataset Group in Geodatabase(s)Group in Geodatabase(s)

• Different departmentsDifferent departments• Size limitsSize limits

Features, Formats & Attributes GIS 458 Spring 2006.

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Transcript of Features, Formats & Attributes GIS 458 Spring 2006.