WFM 6202: Remote Sensing and GIS in Water Management
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Transcript of WFM 6202: Remote Sensing and GIS in Water Management
WFM 6202: Remote Sensing and GIS in Water Management
Akm Saiful Islam
[Part-B: Geographic Information System (GIS)]
Lecture-4(b): Geo-Database
December, 2008
Institute of Water and Flood Management (IWFM)Bangladesh University of Engineering and Technology (BUET)
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Lecture Topic
• Understand basic Geodatabase concepts and structure
• Know the advantages in using the Geodatabase format
• Managing a GeoDatabase
• Creating GeoDatabase
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
First Generation Storage/Linking
AS400Database
Access Database
Tabular Data Spatial Data
•Tabular/Spatial data is linked outside the database
•Links occur using unique IDs….Parcel Numbers
•Storage is still in separate locations
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Second Generation Storage/LinkingGeodatabases
Tabular Data
Spatial Data
•Tabular/Spatial data is stored/linked in a single location!!
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
o Spatial & attribute data integrity
o Intelligent Behavior
o Centralized Data Storage
o Increased Performance
o Advanced Analysis Capabilities
o Multi-user editing (SDE format)
Benefits of a GeoDatabase
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Benefits of Migrating to a GeodatabaseData Integrity
• Maintain tabular data more efficiently– Reduce typological
data errors
• Maintain spatial data more efficiently– Reduce spatial errors
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
What is a Geodatabase?
• A spatial and attribute data
container container – Relational database
management system (RDBMS)
– Maintains data integrity
– Apply Rules and Behavior
• Native data format for ArcGIS
Relational Database - A method of structuring data as collections of tables that are logically associated to each
other by shared attributes. Any data element can be found in a
relation by knowing the name of the table, the attribute (column)
name, and the value of the primary key.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
2 Types of Geodatabase
• Personal GeodatabasePersonal Geodatabase– Stand alone PC, MS Access database– Supports individual and small groups on
moderate size datasets
• Enterprise GeodatabaseEnterprise Geodatabase– Exists on underlying RDBMS through Spatial
Database Engine (SDE) e.g. SQL Server– Usually runs on a dedicated server– Supports many users and massive datasets– Supports raster datasets
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Two types of GeoDatabases
• Personal– Access
• Multi-user– SDE
GIS SQLSDEData Stora
ge
Interpreter
View/Analyze
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
The Personal GeodatabaseIt’s not Scary!
• Stores spatial and tabular data in an Access database format
• Sets the stage for future SDE geodatbase migration
• Edit in ArcView, ArcEditor or ArcInfo
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Geodatabase Features
• Contains tables, feature classes, feature datasets, topology rules, etc. Tables
Feature Classes
Topology
Feature Dataset
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Feature data set
Feature class
Geometric network
Annotation class
Geodatabase ElementsGeodatabase
Relationship class
Table
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
GeoDatabase (GDB) structure
• Stores– Feature datasets– Feature classes– Tables– Raster– More
• A unique structure within the GDB
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Feature Dataset
• Contains Feature Classes – Must have same
coordinate system
• Required for Topology– Behavior
relationships between feature classes.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
GDB Objects: Feature Dataset
• A collection of feature classes– Environment for spatial reference– Environment for topology – Environment for coincident geometry and linked
annotation– Feature classes inherit spatial reference
• Data loaded are projected on the fly, if necessary
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Feature Class
• Stores a single feature type
– Point, Line, Polygon
• Can be standalone or member of a Feature dataset
Stand Alone
Feature DatasetFeature Class
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
GDB Objects: Feature Class (FC)
• A collection of features– Each feature class has one geometry type (point,
multi-point, line, polygon)• Can be stored in a feature dataset or ‘stand-alone’• Attributes are
stored with coordinate data in one table
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Spatial Reference
A
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Coordinate domain• Extent of available coordinates
– Min and max X,Y coordinates– Precision = storage units per
map unit• Example, 1000 mm per meter
• Make sure it covers study area– Allow for growth
• ArcCatalog default– Import: data plus room for growth
• Set your own– Import from existing data– Type in extent for study area
2.14 billion storage units
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Domain
• A property of a feature dataset or feature class (cannot change once set)
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Domains
• Spatial
• Attribute– Range of values (e.g., 0-100)– Coded values (e.g., 1 = potatoes 2 = wheat)
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
The Spatial Domain
• The Geodatabase stores all geometry coordinates as positive integers– Faster Display, Processing, and Analysis– Better Compression (DBMS only)– Efficient for managing topologic relationships
• Limited to 2,147,423,647 storage units.– 2.14x109 meters, or miles, or inches, or ...
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Accuracy and Precision• Accuracy in the Data
– Scale of source map scale will determine accuracy*• 1:600 (1”=50’) ± 1.7 feet
• 1:1,200 (1”=100’) ± 3.33 feet
• 1:2,400 (1”=200’) ± 6.67 feet
• 1:4,800 (1”=400’) ± 13.33 feet
• 1:24,000 ± 40.00 feet– Precision
• Ability to store the accuracy– Significant digits
» Single precision 6-7 precise digits» Double precision 13-14 precise digits» Geodatabase 0-10 precise digits
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Example: Spatial Domain
• All GIS Features Must Fit Within this Positive, 32-bit Integer Space.
OFF LIMITS
2,147,423,647 2,147,423,647
00
The Database’s Spatial Domain
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Standard Fields• Feature classes have default fields
– ObjectID – unique identifier– Shape – contains coordinates of feature– Area – automatically calculated and maintained for polygons
• Shape_Area (Personal GDB)
– Length – automatically calculated and maintained for lines and polygons
• Shape_Length (Personal GDB)
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Spatial Reference
• Property of a feature class or feature dataset• Components
– Coordinate system– Coordinate domain
• Permanent after definition is saved– Warning: it may look like you changed the coordinate
system, but you can’t and don’t try. It messes things up!
• See next slide for more information
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Storing Feature Coordinates
Two important considerations when storing
feature coordinates in a Geodatabase:
1. All data is stored as positive, 32-bit integers (Spatial Domain)
2. All data must maintain a Coordinate Precision.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Coordinate Precision
• The geodatabase converts all coordinates into 32-bit Storage Units.
• Storage Units are the smallest measurable unit that can be stored in a Geodatabase.
• Precision is used to convert coordinate system units into storage units.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Example: Coordinate Precision
Floating Point Coordinate in ArcGIS
(123.456000)
Multiply by Precision
123.456789 × 1000
Divide by Precision 123456 ÷ 1000
Integer Storage Unit in a Geodatabase
(123456)
X = 123.456789Precision =1000
• Precision is a Scale Factor– Used to preserve decimal places before
rounding– Larger precision preserves more digits
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Example: Precision Preservation
Coordinate system units ÷ Precision = Storage units
Meters 100 1 cm
Meters 1000 1 mm
Meters 50 2 cm
Feet 12 1 inch
Coordinate System Units PrecisionStorage Units =
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Topology Objects
• Maintain data integrity– Within feature class– Between feature class
• Feature Dataset required
• Functionality– Display Topology
Errors– Select and Correct
Errors– Validation
• Regarding map features, topology is relationship between features connectivity and adjacency.
• Geodatabase topology provides tools to ensure integrity of spatial data.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Selected Topology Rules
• 25 available 25 available topology topology rulesrules
• 2 Rules 2 Rules currently currently appliedapplied
– Must Not Overlap
– Must Not Have Gaps
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
File Management
• Compacting the Personal Geodatabase– Reduces file size
• Procedure– In ArcCatalog, right
click on the .mdb file– Select the Compact
Database option in the context menu
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Reference Data Locations
• Proscribed by the Standard for Geospatial Dataset File Naming– http://dlnt20.fsa.usda.gov/scdm/DP/Parent3.htm
• Standard folder structure on shared f: drive
• GeodataGeodata – top level geospatial data folder
• Local Geodata Administrators have authority to create, delete, and change folders, but only as outlined in the standards document.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
<disk drive>:geodata
<geospatial dataset category (directory / folder)>
soils <geospatial dataset category (directory / folder)>
soil_a_ks057
<geospatial dataset>
<geospatial dataset>
<geospatial dataset>
topographic_images <geospatial dataset category (directory / folder)>
plants
soil_p_ks057
soil_l_ks057
• The current standard has 23 common geospatial dataset categories such as soils that consist of 1 or more geospatial datasets.
Data Management File Naming Standards
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
A geospatial dataset file name should:
• be less than 30 characters long
• consist of lower case a-z and numerals 0-9• first character always a-z
soil_a_ks057
• Elements of a file name
Feature category Feature type: a-polygon, l-line,
p-point, t-table, i-image, etc.
Data Management File Naming Standards cont.
Location: Alpha or numeric FIPS code
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Data Storage and Backup
• Shared data in a service center must be on the f: drive.• Personal data can be stored on the c: drive or h: drive.
– c: drive is notis not routinely backed up.– h: drive should contain important working files
that can be routinely backed up.• Local Geodata Administrators are responsible for
ensuring backups are routinely being made of specific directories.– Large, easily replaced datasets should not be
routinely backed up because they can be obtained again.
– Files and directories that change regularly should be routinely backed up.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
GDB Design
• A critical step• UML modeling for
ArcGIS– IBM Rational Rose– MS Visio
• Class diagrams
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Managing Your GDB
• ArcCatalog is your main tool to manage the schema– Construction of component parts– Organization of those parts– Properties for the parts
• Many capabilities are available– Some are not on the default GUI
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Reading Schemas
Structural
Logical
Most data access technologies provide a way for you to query the schema of a database, and obtain information about the tables, stored procedures, data types, users, and other content of a database.
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating a GDB
• Personal– Use ArcCatalog
• Multi-user– Must be done at the
system level
A
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
1.1. Open ArcCatalog Open ArcCatalog 2.2. Choose a folder Choose a folder
location location 3.3. Right click: Choose Right click: Choose
New < Personal New < Personal GeodatabaseGeodatabase
Creating a new personal geodatabase
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Right click your geodatabase
Choose: New < Feature Dataset
Creating Feature Datasets
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating an empty feature class
• Two locations available: stand-alone and within a feature dataset
A
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating a feature dataset
A
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Right click your geodatabase
Choose: New < Feature Dataset
Creating Feature Datasets
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Feature Datasets: Setting the spatial reference
http://arcscripts.esri.com/ :Search on Spatial Domain
1. Set the Projection
2. Set the Domain
• Precision
• Extent
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Import existing data
•Navigate to the feature dataset or geodatabase icon in ArcCatalog
•Right Click•Choose Import
Use this to import any existing format!
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Subtypes & Domains
Subtype:
•Distinguish features within a single layer
•Maintain different domains within the same field
•Need ArcEditor or ArcInfo
Domain:
•Identify & constrain attribute values
•Can utilize in ArcView
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Subtypes & DomainsParcels
Example
Subtype: Boundary Line
Domains: ROW Type
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Subtypes
• Must be long or short integer fields
• Created in ArcEditor or ArcInfo
• Increases the efficiency of the editing process
• Use when
– Standardizing a legend
– distinguishing different default values/domains within the same field
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating Subtypes
• In ArcCatalog• Double click on a feature
class• Select the Subtype tab
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating Domains
Created inArcCatalog
1. Double Click on the Personal Geodatabase Icon
2. Choose the Domains tab
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating Domains—Assigning to Feature Classes
In ArcCatalog
1. Double click a feature class
2. Choose the Fields tab
3. Highlight a field
4. Click Domain under the Field properties section
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating Domains—Assigning default values
Set in the Field Properties section
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Using Domains during the Editing Process
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Geodatabase TopologyPutting the power into your hands
– Topology Rules• Preset rules to define topological relationships to
ensure connectivity, adjacency and coincidence– Can be changed at any time
– Topology Tools• Maintain spatial relationships• Toolbar and Tasks
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Creating Topology
1. Rules– Land use boundaries overlap parcel boundaries– Manholes overlap sanitary line endpoints
2. Cluster Tolerance– Min distance where vertices within tolerance are
snapped
3. Ranks– Control what features move during validating
• Surveyed points will not move (snap) during the validation process
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Validating Topology
• Validate edited features using set topology rules
• Evaluate rules/tolerance and generates error notifications
• Snaps vertices using set cluster tolerance and ranks
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Create a New Topology
• Created in ArcCatalog
• Created within a Feature Dataset
• Topology Wizard – Allows user to set Rules, Ranks,
Tolerance, and perform initial Validation
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Final Topology
When added to ArcMap, will show errors from the validation process
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Managing Topologies
• Right click on the Topology in ArcCatalog
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Topology ToolsMaintenance
• Standard toolbar in ArcView-ArcInfo
• Used in an editing environment in ArcMap
• Use in conjunction with Topology Tasks in Editor Toolbar
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Editor ToolbarMaintenance
• Topology Tasks: Modify, Auto Complete Polygon and Reshape
– Allows user to use basic editing tools to alter vertices, replace lines, add adjacent polygons or alter existing polygons
– Use in conjunction with the Topology Edit Tool on the Topology Toolbar
Remember:Set snapping and snapping tolerance
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Flexible Editing• Topology edit tool
– Allows for editing shared boundaries– Builds a temporary topology cache within a
given extent• Faster performance• Must use each time your extent changes
• Show shared features tool– Move a boundary without effecting shared
boundaries (temporary)• Parcels & land use • Parcels and easements
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Validate & Fix
• Validate after editing is complete– Errors are highlighted
• Click the Fix Error button
• Select a feature and right click– Fix– Mark as an Exception– Do Nothing
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Process in Review
1. Plan for success
2. Import data
3. Set Subtypes & Domains
4. Create Topology
5. Start editing!
Pro-West & Associates
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Tips
• Projecting data– Must create a new feature class
• PGDB is 2 GB max
• Read-only on a PGDB will restrict some analyses, such as Select by Location
• Use compact to clean up temporary files
• All table names need to be unique
WFM 6202: Remote Sensing and GIS in Water Management © Dr. Akm Saiful IslamInstitute of Water and Flood Management (IWFM) , Bangladesh University of Engineering and Technology (BUET)
Ex 2
• Create a Personal GDB
• Create an empty Feature Class
• Create a Feature Dataset
• Create a Feature Class within the Feature Dataset