Table A set of data elements arranged in rows and columns. Each row represents a single record. Each column represents a field of the record. Rows and columns intersect to form cells, which contain a specific value for one field in a record.
Tables typically store stand-alone attribute information or information associated with a spatial location such as addresses. Terrain A triangulated irregular network TIN -based dataset that uses feature classes as data sources to model multiple resolution surfaces using z-values.
Toolbox A collection of dataflow and workflow processes. These are used for performing data management, analysis, and modeling. Topology The arrangement that constrains how point, line, and polygon features share geometry within a geodatabase. For example, street centerlines and census blocks share geometry, and adjacent soil polygons share geometry. Topology defines and enforces data integrity rules, topological relationship queries and navigation, and sophisticated editing tools.
It also allows feature construction from unstructured geometry. These database design models are intended to help GIS users rapidly become productive with the geodatabase and share what really works among users and our developer communities. For example, the land records and the Arc Hydro data models are based on proven standards over the past decade.
All appropriate standards are incorporated into the data model work. Each ArcGIS data model uses commonly adopted spatial representations e. Each data model specifies the commonly used integrity rules for key data layers and feature classes. ArcGIS data models can be widely adopted regardless of the system architecture.
Downloads Downloads for Data Models gives you access to tools, white papers, case studies, and design templates. Storage in a Relational Database Management System A multiuser geodatabase utilizes a multitier architecture that implements advanced logic and behavior in the application tier e. A relational database management system provides a straightforward formal structure for storing and managing information in tables. Data storage and retrieval are implemented with simple tables.
Certain characteristics of geographic data management, such as disk-based storage, definition of attribute types, query processing, and multiuser transaction processing, are delegated to the RDBMS.
At ArcGIS 9. ArcObjects is an example of application logic that enables the behavior in a geodatabase. Spatial Types A spatial type is an object type that describes and supports spatial data such as points, lines, and polygons.
It allows you to create columns capable of storing spatial data such as the location of a landmark, a street, or a parcel of land. The geodatabase defines a generic model for geographic information and is implemented as either a collection of files in a file system or a collection of tables in a DBMS. See Creating a file geodatabase for more information.
File geodatabases have configuration keywords that customize the storage of an individual dataset. You can specify a keyword when you copy and paste or import data, although the default is usually adequate.
For more information, see Configuration keywords for file geodatabases. You create an empty feature dataset, feature class, raster catalog, raster dataset, and table in a file geodatabase the same way you create them in a personal geodatabase: right-click the geodatabase or feature dataset, point to New, then click the item you want to create. See any of the following topics for more information:.
Creating new datasets using ArcCatalog. Creating raster datasets in a geodatabase. Creating raster catalogs in a geodatabase. Once you've created an empty feature class or table, you load data into it from the Catalog tree. For more information, see About loading data into existing feature classes and tables and Importing raster datasets.
Unlike personal geodatabases, whenever you create a new file geodatabase feature class, raster catalog, raster dataset, or table, either through the Catalog tree or a geoprocessing tool, you can optionally specify a configuration keyword.
The configuration keyword customizes how the data is stored and accessed. For a description of the keywords available, see Configuration keywords for file geodatabases. Once in a file geodatabase, a dataset looks the same in ArcCatalog and ArcMap as in a personal geodatabase. Also, with the exception of spatial indexes and SQL queries, which are discussed next, you work with datasets the same way.
All commands and tools that accept personal geodatabase datasets as input also accept file geodatabase datasets. Click Create. The dialog closes and the new geodatabase is added to the Destination Geodatabase list in the Select Output Geodatabase dialog. Tips for Working with Geodatabases Personal geodatabases store datasets within a Microsoft Access data file. Enterprise geodatabases require a login. Users with read-only access cannot save data to an enterprise geodatabase.
You cannot load vector data with unsaved edits to a geodatabase. You can save point, line, polygon, and multipoint vector data to a geodatabase. Vector files in ENVI vector format. In ENVI, you cannot save virtual mosaics or spectral libraries to a geodatabase. In ENVI, display enhancements you add to a raster image contrast stretching, sharpening, etc.
ENVI retains color maps upon saving to a geodatabase. Standard spatial reference information from input rasters will be retained upon saving to a geodatabase. Information about Rational Polynomial Coefficient RPC spatial references , pseudo spatial references , and custom projections are not retained.
After saving a feature class to a geodatabase, use ArcGIS to drag the feature class to a feature dataset if needed. For NITF data, you can only save individual image segments to a geodatabase.
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