ArcGIS Geodatabase Topology Rules ®
Topology in ESRI®ArcGIS®allows you to model spatial relationships between featureclasses in a featuredataset. Topology rules allow you to definethose relationships between features eatures in a singlefeatureclass or subtypeor between two featureclasses or subtypes. Topology rules allow you to definethespatial relationships that meet theneeds ofyour data model. Topology errors ors areviolations ofthe rules that you can easily find and manageusingthe editingtools found in ArcMap .
How to read these diagrams: Thetopology ruleoccurs within a singlefeatureclass or subtype.
TM
:
Topology rule name Descriptionand exampleofa valid caseofthe specifiedtopology rule.
Descriptionand exampleofa caseof thespecifiedtopology rulewhereerrors exist and will bereturned. For each example,the error shapeis shown in bright red.
: Thetopology ruleoccurs between two different featureclasses or subtypes.
Polygonsmustnot overlapwithina featureclass or subtype. Polygonscanbe disconnected or touch at a point or touch along an edge.
n n o o e g g n y y i l l L o o P P
Polygon errors are created from areas wherepolygons overlap.
:
Usethisruletomakesurethatall polygonshaveatleastone pointwithintheir boundaries. O verlapping polygonscansharea pointinthat overlapping area.
Must be covered by feature class of n n o o g g y y l l o o P P
Thepolygons in thefirst featureclass or subtypemust be covered by the polygons ofthe secondfeature class or subtype.
:
Must not overlap with Polygons ofthefirst featureclass or subtypemust not overlappolygons ofthesecond featureclass orsubtype.
Polygonerrorsare createdwhere polygonsfrom thetwo feature classes or subtypes overlap. Lakesandlandparcels fromtwodifferentfeature classes must not overlap.
:
Counties must becovered by states.
Polygonerrorsare created whereany part ofa polygon is not covered by oneor more polygonsinthe other featureclass orsubtype.
Usethis rulewheny ou wantthepolygons from twofeatureclasses or subtypestocover the samearea.
n n Must be larger than cluster tolerance o o g g Cluster toleranceis the minimumdistance y y Anypolygonorline l betweenvertices l featurethat would offeatures. o o collapsewhen validatingthe P P Vertices that fall within topology is an error. thecluster toleranceare r r defined ascoincidentand o o aresnapped together. e e Thisrule isapplied toall lineand polygonfeatureclassesthat n n participateinthe topology. i i L L
:
Must be covered by boundary of touch t t subtypemust boundariesof n n polygonsfrom i i anotherfeature o o class or subtype. P P
Point errors are created wherethe points areoutsideor touchtheboundary ofthepolygons. Statecapitals must beinsideeach state.
Usethisrulewhenyouwantpointstoalignwiththe boundariesof polygons.
Lotlinescannotoverlap oneanother.
Linescanonly touch at their ends and must not overlap each other within a featureclass or subtype.Lines can touch,intersect,and overlapthemselves.
e e n n i i L L
Lot lines cannot intersect or overlap, but theendpoint ofonefeaturecan touch theinterior ofanother feature.
e e n n i i L L Soil polygons must belarger than thecluster tolerance.
:
Utility servicepoints might berequired to beon the boundaryofaparcel.
Points in one featureclass or subtypemust be covered by the ends oflines in anotherfeature class or subtype.
Usethis rulewheny ou wanttomodel pointsthatare coincidentwiththe endsof lines.
Lineerrors are created wherelines overlapthemselves, and point errors are created wherelines crossthemselves.
Lineswithinafeature class or subtype must only have onepart.
9
Contourlinescannotintersect themselves.
9
10
9
8 8
Multipartline errors arecreated wherelines have morethan one part.
25
40
A highway system is madeup ofindividual features whereany onefeatureis not madeupof morethan onepart.
Usethisrulewhenyou wantlinestobecomposed of asingleseries of connected segments. s.
:
Must be covered by feature class of
80 20
e e n n i i L L
Highways can cross and comeclose to rivers,but road segments cannot overlapriversegments.
Endpointsofsecondaryelectric lines must becapped by either a transformer or meter.
:
Polylinesusedfordisplayingblock and lot boundaries must becovered byparcelboundaries.
Point must be covered by line t t n n i i o o P P
Street intersections must be covered by theendpoints ofstreet centerlines.
Lines that makeupbus routes must beon topoflines in a road network.
Lineerrors are created on lines that arenot covered by the boundariesof polygons.
Usethis rulewhenyou wantto model linesthatare coincidentwiththe boundariesof polygons.
:
Point errors are created on the points that arenot covered by the ends oflines.
Lines in one featureclass or subtypemust be covered by the boundariesof polygonsinanother featureclass or subtype.
Points in one featureclass or subtypemust be covered by lines in anotherfeatureclass orsubtype.
Usethis rulewhenyou wanttomodel pointsthatare coincidentwithlines.
:
Lineerrors are created on the lines in thefirst featureclass that arenot covered by lines in thesecond featureclass.
Must be covered by boundary of e e n n i i L L
Point errors are created at the ends oflines that arenot covered by a point.
Lines in one featureclass or subtypemust be covered by lines in anotherfeature class or subtype.
Usethis rulewhenyou havemultiplegroupsof linesdescribing thesamegeography.
:
Must be covered by endpoint of t t n n i i o o P P
Point errors are createdwherepoints do not touch the boundariesof polygons.
e e n n i i L L
Lineerrors are createdwherelines fromtwofeature classes or subtypes overlap.
Usethisrulewhenyou wanttomodel theendsoflinesinone featureclassor subtypethatare coincidentwithpoint featuresinanother featureclass.
Lines must not cross oroverlapthemselves within a featureclass or subtype.Lines can touchthemselvesand touch,intersect,and overlapotherlines.
Usethis rulewheny ou only wantlinesto touchattheir ends withoutintersecting or overlapping themselves.
Lot lines cannot intersect or overlap and must connect to oneanother only at theendpoint ofeach linefeature.
Endpoint must be covered by Theends oflines in onefeatureclass or subtypemust be coveredbypoints inanotherfeature class or subtype.
25
Fortransportationanalysis,streetand highway segments ofthesamefeature shouldnotoverlapthemselves.
Must be single part
Lineerrors are createdwhere linesoverlap,and point errors are createdwhere lines cross or touch.
Usethis rulefor linesthatshould never occupy thesame hesame spacewithlines inanother featureclass or subtype.
Vegetationandsoilsmust covereachother.
285
Lineerrors are createdwhere linesoverlap themselves.
Usethis rulewithli neswhosesegments should never occupy thesamespace asanother segmentonthe sameline.
e e n n i i L L
Lineerrors are created wherelines overlap,and point errors are createdwhere lines cross.
Must not overlap with Lines in one featureclass or subtypemust not overlapany part of another linein anotherfeature class or subtype.
Lines must not overlap themselveswithina featureclass or subtype. Linescantouch, intersect,andoverlap linesinanotherfeature class or subtype.
Must not self intersect
Usethis rulewheny ou only wantlinesto touchattheir ends and notintersector overlap overlap..
:
Must cover each other
e e n n i i L L
Lineerrors are createdwhere linesoverlap.
Must not intersect or touch interior e e n n i i L L
Points in one featureclass or
Usethis rulewhenyou wantpointsto becompletely within theboundariesof polygons.
94238
Usethisrulewhenyouwantonesetof polygonstobe covered by somepartof another singlepolygon inanother featureclassor subtype.
Lines must not cross or overlapany part ofanother linewithin thesamefeature class or subtype.
For hydrologic analysis,segments ofa river system might beconstrained to only have nodes at endpoints or junctions.
Must not self overlap
Usethis rulewith lineswhosesegments should never crossor occupy thesamespacewith other lines.
:
Cluster Tolerance
Subdivisionboundariesare coincidentwithparcelboundaries, but do not cover all parcels.
Must be properly inside polygons Points in one featureclass or subtypemust be insidepolygonsof anotherfeature class or subtype.
Major road lines form part of outlinesforcensusblocks.
Cluster Tolerance
Lineerrors are createdwherepolygon boundaries in thefirst featureclass or subtype arenot covered by the boundariesofpolygons in another featureclass orsubtype.
Usethis rulewhenthe boundariesof polygonsin onefeature classor subtypeshould alignwiththeboundariesof polygons inanother featureclassor subtype.
t t n n i i o o P P
e e n n i i L L
Polygonerrorsare createdfrom polygonsfromthe first featureclass or subtypethat arenot covered by a single polygon from the second featureclass or subtype.
Lines must not overlap any part ofanother linewithin a feature class or subtype.Lines cantouch, intersect,and overlapthemselves.
Point errors are created wherethe end ofa line touches theend of only oneother line.
Usethis ruletoc leanupdata withinappropriately subdivided lines.
Must not intersect
All polygons in the
Area boundary must be covered by boundary of Theboundaries of polygonsinone featureclass or subtypemust be covered by the boundariesof polygonsinanother featureclass or subtype.
Polygonsinone featureclass or subtype must becovered by a singlepolygon fromanother featureclass or subtype.
n n first featureclass and all in thesecond o o polygons featureclass must g covereachother. g Must becovered by y y -FC1 featureclass l ofFC2. l be covered by o o -FC2Must featureclass ofFC1. P P
Usethis rulewhenpolygons from onefeatureclass or subtype should notoverlappolygons of another featureclassor subtype.
n n o o g g y y l l o o P P
States arecovered by counties.
A street network has linesegments that connect.If segments end for dead-end roads or cul-de-sacs,you could chooseto set as exceptions duringan edit session.
Usethis rulewith linesthatshould never occupy thesame hesame spacewithother lines.
:
Lineerrors are createdwhere polygon boundariesare not covered by a lineofanother featureclass or subtype.
Must be covered by n n o o g g y y l l o o P P
Usethis rulewheneach polygoninone featureclassor subtypeshould becovered by all thepolygonsof another featureclassor subtype.
n n o o g g y y l l o o P P
:
Polygonerrorsare created from the uncoveredareasof thepolygons in thefirst feature class or subtype.
Polygonboundaries in onefeatureclass or subtypemust be covered by thelines ofanotherfeature class or subtype.
Usethis rulewhenpolygon boundariesshould becoincident withanother linefeatureclassor subtype.
Parcels must contain at least oneaddress point.
e e n n i i L L
Soilpolygonscannotincludegaps or form voids—they must form a continuousfabric.
Boundary must be covered by n n o o g g y y l l o o P P
Polygonerrorsare created from the polygonsthatdonot contain at least one point.A point on theboundary ofa polygonisnot containedinthat polygon.
e e n n i i L L
25
Theend ofa line cannot touch theend of only oneother line within a featureclass or subtype.The end ofa linecan touch any part of itself.
40
Must not overlap Lineerrors arecreated from theoutlines ofvoid areas in a singlepolygon orbetweenpolygons. Polygonboundariesthat arenot coincident with other polygon boundariesareerrors.
Usethis rulewhenall of your polygonsshould form acontinuoussurface withno voidsor gaps.
A votingdistrict mapcannot haveany overlaps in its coverage.
Containspoint Each polygon ofthe first featureclass or subtypemustcontain withinitsboundaries at least one point ofthesecond featureclass or subtype.
Polygonsmustnot havea void between them within a featureclass orsubtype.
Must not have pseudonodes Point errors are created at theend ofa linethat does not touch at least oneother line or itself.
Usethisrulewhenyou wantlinesina featureclassor subtypetoconnect tooneanother.
Descriptionofareal-world applicationofthespecified topologyrule.
Must not have gaps
Usethis ruletomake surethatno polygonoverlapsanother polygoninthe samefeatureclass or subtype.
n n o o g g y y l l o o P P
e e n n i i L L
Generalized descriptionof whentousethis rule.
Must not overlap n n o o g g y y l l o o P P
Must not have dangles Theend ofa linemust touch any part ofone other lineor any part ofitselfwithin a featureclass or subtype.
:
Point errors are created on the points that arenot coveredbylines. Monitoringstationsmustfall alongstreams.
Copyright ©2004ESRI. All rights reserved.ESRI,ArcGIS,A rcMap,and theArcGIS logo aretrademarks,registered trademarks,or servicemarks ofESRI in the United States,theEuropean Community,or certain other jurisdictions.
