The geodatabase is the native data storage format for ArcGIS. It offers many advantages for modeling, analyzing, managing, and maintaining GIS data.

Learning Objectives

  • Describe the components of the geodatabase.
  • Create geodatabase schema.
  • Design and create a geodatabase.

Advantages of using a geodatabase

Feature Description
Centralised repository All data is stored in the same database, as opposed to in many separate files.
Scalable data model As your GIS needs increase, you can migrate data from one geodatabase to an upgraded format that allows for more users and editors.
Increased data integrity You can create spatial and attribute behaviours to facilitate editing, help eliminate data entry errors, and maintain spatial and attribute relationships between your data.
Support for imagery Mosaic datasets in the geodatabase allow you to manage multiple images as one.

Types of geodatabase

  • File Geodatabase:
    • a collection of GIS datasets stored in a file system folder.
    • work across operating systems and can store individual datasets up to 1 terabyte (TB) in size by default. The size limit can be increased with keywords to 256 TB.
    • support multiple people editing different feature classes or tables at the same time.
    • based on SQL Server Express (.mdf)
  • Enterprise geodatabase:
    • support versioning and replication.
    • require a database management system (DBMS), such as DB2, Informix, Microsoft SQL Server, Oracle, or PostgreSQL.
    • typically found in larger organizations.
    • support multiple users viewing and editing the GIS database at the same time.

Sample geodatabase from course

Mosaic Datasets

A mosaic dataset is a data model within a geodatabase that is used to store, manage, view, and query large collections of raster data. It can be a heterogeneous collection of raster datasets (individual images) with multiple formats, sources, data types, resolutions, number of bands, pixel depths, file sizes, and coordinate systems.

Certificate

Mosaic of imagery