Benefits and Concerns when Constructing an Enterprise-scale Geodatabase Larry Theller, presenter Agricultural and Biological Engineering Dept Purdue University.

Benefits and Concerns when Benefits and Concerns when Constructing an Enterprise-scale Constructing an Enterprise-scale

GeodatabaseGeodatabase

Larry Theller, presenterAgricultural and Biological Engineering DeptPurdue University

Co-authors:Bernie Engel, Richard Farnsworth, Jin Yong Choi, Dwight Welch

BackgroundBackground

Campus has 125+ ArcGIS usersCampus has 125+ ArcGIS users My dept. provides GIS data for many My dept. provides GIS data for many

groups who use same layersgroups who use same layers First step was FTP/download site for First step was FTP/download site for

1998 orthos and statewide topo map 1998 orthos and statewide topo map layer.layer.

Statewide DEM, NASS, 2003 orthos… Statewide DEM, NASS, 2003 orthos…

Our solutionOur solution

SDE Geodatabase to act as librarySDE Geodatabase to act as library Mostly static layers, users not editingMostly static layers, users not editing Fast raster delivery is criticalFast raster delivery is critical Off-campus use is a plusOff-campus use is a plus Clients will be various GIS programsClients will be various GIS programs

The GeodatabaseThe Geodatabase

ArcGIS native data formatArcGIS native data format Stores feature classes that have one Stores feature classes that have one

geometry typegeometry type Can store feature and attribute behaviorCan store feature and attribute behavior Spatial and attribute data stored in RDBMSSpatial and attribute data stored in RDBMS Two physical implementationsTwo physical implementations

– Personal geodatabasePersonal geodatabase– ArcSDE GeodatabseArcSDE Geodatabse

Capabilities of Enterprise Capabilities of Enterprise GeodatabaseGeodatabase

Rule-based, Enhanced (network) Rule-based, Enhanced (network) topologytopology

Multi-user (versioned) editingMulti-user (versioned) editing Attribute validation (domains, Attribute validation (domains,

subtypes)subtypes) Scaleable storage solutionsScaleable storage solutions Referential Integrity in relationshipsReferential Integrity in relationships Custom features ( behavior of Custom features ( behavior of

objects)objects)

When do you need Geodatabase?When do you need Geodatabase?

Raster data access drives oursRaster data access drives ours– Can’t afford to move aerial photographyCan’t afford to move aerial photography

150 casual users storing multiple 150 casual users storing multiple copies of data.copies of data.

We use distributed GIS client but with We use distributed GIS client but with limited WEB accesslimited WEB access– So want one-stop data accessSo want one-stop data access– but…restrict “download” of some databut…restrict “download” of some data

Purdue’s IT group now offers ArcGIS on CitrixThis increases the need for “one-stop data shopping”

Most basic use is container for Rasters and Vectors

Just SDE? Or add IMS?Just SDE? Or add IMS?

Physical overhead of SDE database Physical overhead of SDE database connections versus cost of ArcIMS connections versus cost of ArcIMS license.license.

Will the database be the sole source?Will the database be the sole source?

-Will you need to interface files -Will you need to interface files (images, changing vectors) with (images, changing vectors) with geodatabase features?geodatabase features?

Consider AXL service in ArcIMS.Consider AXL service in ArcIMS.

An ArcIMS Feature Service streams the actual data features An ArcIMS Feature Service streams the actual data features to you over the Internet, similar to the way audio and video to you over the Internet, similar to the way audio and video are streamed. Each feature service contains one or more are streamed. Each feature service contains one or more ArcIMS ArcIMS feature classesfeature classes. .

A layer based on an ArcIMS feature class works the same as A layer based on an ArcIMS feature class works the same as any other feature layer. An ArcIMS feature class is simply any other feature layer. An ArcIMS feature class is simply another feature data source for a layer, just as a shapefile another feature data source for a layer, just as a shapefile is a feature data source for a layer. is a feature data source for a layer.

If you add an ArcIMS Feature Service to ArcMap, you'll get a If you add an ArcIMS Feature Service to ArcMap, you'll get a new group layer containing one sublayer for each of the new group layer containing one sublayer for each of the feature classes in the service. feature classes in the service.

As its name suggests, an ArcIMS Feature Service cannot As its name suggests, an ArcIMS Feature Service cannot contain raster data. contain raster data.

ArcIMS Feature ServiceArcIMS Feature Service

Client SoftwareClient Software

Browser/viewerBrowser/viewer ArcExplorer 9ArcExplorer 9 WMS viewersWMS viewers IE (thin client)IE (thin client)

Full-feature GISFull-feature GIS ArcGISArcGIS Custom ModelsCustom Models

Client SoftwareClient Software

Browser/viewerBrowser/viewer ArcExplorer 9ArcExplorer 9

– freefree– No images from No images from

SDE directSDE direct– No metadataNo metadata– Will support images Will support images

from ArcIMS AXLfrom ArcIMS AXL WMS viewersWMS viewers

– User must User must customizecustomize

Full-feature GISFull-feature GIS ArcGISArcGIS

– Direct ConnectDirect Connect– ArcIMS connectArcIMS connect– Metadata from SDEMetadata from SDE– Steeper learning Steeper learning

curvecurve– priceprice

Goal: meet or exceed performance Goal: meet or exceed performance of network-based filesof network-based files

0 10 20 30 40 50 60 70 80 90

Samba Share

Windows Share

ArcSDE

Local Drive

time (sec)

Zoom to county

Zoom 1:24,000

Zoom 1:2500

Zoom 1:24,000

Open map file

Direct Connect to SDEDirect Connect to SDE

SDEDatabase

ArcCatalogArcCatalog

ArcCatalog ArcCatalog

ArcCatalog

One connection per client

ArcMapArcMap

ArcMap ArcMap

Issues on Windows XP

ArcIMS as broker to SDEArcIMS as broker to SDE

SDEDatabase

ArcCatalog

ArcIMSFeature serverImage Server

ArcCatalog

ArcCatalogArcCatalog

ArcCatalog

ArcIMS uses 4 connections regardless of client load.

ArcMap

ArcMap

Using ArcCatalog

“Add GIS Server”

Add URL of ARCIMS serverNOT WEBPAGES!

You can get a list of Feature Data Sets.

Each dataset may containmany feature classes.

Restricted services are supported.

AXL-based services look like other map layer types to Arcmap, ArcCatalog and ArcExplorer

You can Drag-and-Drop into ArcMap.

Legends are delivered by AXL file.

Groups of layers (“feature datasets” and raster layers)within the geodatabase

MetadataMetadata

MetadataMetadata ArcSDE – database has one format for ArcSDE – database has one format for

direct connectiondirect connection ArcIMS –axl service uses different format ArcIMS –axl service uses different format

than web servicethan web service ArcIMS metadata server is still another ArcIMS metadata server is still another

different entitydifferent entity ArcExplorer – can’t see anything but an ArcExplorer – can’t see anything but an

embedded url.embedded url.– Updates must cascade through different file Updates must cascade through different file

formats and software products.formats and software products.– Needs (!!) to be streamlined by ESRI.Needs (!!) to be streamlined by ESRI.

Metadata processMetadata process Import into SDE for ArcCatalogImport into SDE for ArcCatalogEmploy XML version for ArcIMS Employ XML version for ArcIMS

Metadata server to enable Metadata server to enable searching.searching.

ArcExplorer users – can export a URL ArcExplorer users – can export a URL from an attribute - with poor results.from an attribute - with poor results.

Provide in HTML for ArcIMS web thin Provide in HTML for ArcIMS web thin clients.clients.

SDE Connects to ArcIMSSDE Connects to ArcIMS

SDEDatabase

ArcCatalog

ArcIMSFeature serverImage Server

ArcCatalog

ArcCatalog

Web Browser

ArcExplorer

ArcIMS uses 4 connections regardless of client load.

ArcMap

ArcMap

Web Browser

AXL Services

HTMLservices

Drawbacks of this approachDrawbacks of this approach

Design of master GDB is complex.Design of master GDB is complex. Requires database management Requires database management

experience (not as much GIS.)experience (not as much GIS.) Thin client (IE) aspects not robust.Thin client (IE) aspects not robust. Metadata: 3 client types, 3 separate Metadata: 3 client types, 3 separate

copies!copies! Data presentation not uniform.Data presentation not uniform. ArcIMS components add labor.ArcIMS components add labor.

– Requires more management than static GDB.Requires more management than static GDB.

ConclusionsConclusions

SDE Geodatabase is MUCH faster SDE Geodatabase is MUCH faster access to raster data than MrSid.access to raster data than MrSid.

ArcIMS is key broker for multiple ArcIMS is key broker for multiple client TYPES.client TYPES.

ArcIMS adds significantly to ArcIMS adds significantly to management load.management load.

Future development will be in ArcGIS Future development will be in ArcGIS Server (split-off thin client.)Server (split-off thin client.)

LessonsLessons

Create metadata for all layers, in Create metadata for all layers, in XML and HTML. XML and HTML.

Import Metadata to SDE from Import Metadata to SDE from beginningbeginning

In retrospect, flat feature tree would In retrospect, flat feature tree would be preferable.be preferable.

Oracle’s unlimited table size is a Oracle’s unlimited table size is a plus.plus.

Enterprise Geodatabase?Enterprise Geodatabase?

Raster and Vector?Raster and Vector? Who is software client?Who is software client?

– Full capability with all users?Full capability with all users?– Or are some just browsersOr are some just browsers

Will we allow multiple edits?Will we allow multiple edits? Read the books or buy training?Read the books or buy training? Which database? SQL or Oracle?Which database? SQL or Oracle? Who trains “shapefile” users? Who trains “shapefile” users?

Questions we asked