Advantages of Geodatabase | disadvantages of Geodatabase
This page covers advantages and disadvantages of Geodatabase. It mentions Geodatabase advantages or benefits and Geodatabase disadvantages or drawbacks.
What is Geodatabase?
• The ESRI® ArcGIS® applications (such as ArcMapTM , ArcCatalogTM and ArcToolboxTM) work with geodatabases as well as with coverages and shapefiles.
• It is made of two words "geo" meaning spatial and database which refers to RDBMS (Relational Database Management System).
• It is basically native data storage and data management framework for ArcGIS.
• It acts as organizational tool to store and manage the data.
• It is gateway to advanced GIS capabilities. The figure-1 depicts geodatabases used in GIS.
• The geodatabase is a container which houses a collection of various geographic datasets.
It supports all the different types of data which can be used by ArcGIS which include following.
-satellite and aerial images (raster data)
-surface modeling or 3D data
-utility and transportation network systems
• Moreover there is complete set of conversion tools available which can help in migrating existing
geospatial data into geodatabase. It can be scaled to suit a single user or multi-user access.
• The fundamental ArcGIS datasets include tables, feature classes and rasters. These and other more complex datasets, such as topologies and geometric networks, are all contained within the geodatabase. The figure-2 depicts geodatabase life cycle.
• There are three types of geodatabases viz. Personal geodatabases, File geodatabases, and ArcSDE geodatabases.
Benefits or advantages of Geodatabase
Following are the benefits or advantages of Geodatabase:
➨It offers centralized GIS data management as multiple spatial and tabular data formats can be stored in the same geodatabase which makes GIS data easy to manage and access.
➨Geodatabases can accommodate large sets of features without tiles or other spatial partitions.
➨It supports two, three and four dimentionsional vector features (x, y, z and m values), true curves and complex polylines.
➨One can classify different kinds of features within a feature class by creating subtypes.
➨Validation rules can prevent many errors and identify others. Hence geodatabase offers more accurate data editing.
➨Using geodatabase it is possible to create custome point, line and polygon features.
➨One can model flow of resources along a geometric network. This geometic network combines line and point feature classes into a single database entity. It also maintains explicit topological relationships between the features.
➨Multiuser geodatabases support versioning. Hence more than one person can edit geodatabase at the same time.
➨Geodatabase supports large data management in a continuous integrated environment viz. raster/vector/tabular/CAD (SDE).
➨Geodatabase schema can be graphically modeled using UML and later generated using CASE tools.
Drawbacks or disadvantages of Geodatabase
Following are the drawbacks or disadvantages of Geodatabase. Let us understand the same with respect to
personal geodatabse and file geodatabase.
➨Personal Geodatabases are subject to a number of functional limitations as follows:
• An individual database cannot be larger than two GB in size, although the effective database size is smaller, somewhere between 250 and 500 MB, above which the database performance starts to slow down.
• Supports only single-user editing and does not support versioning
➨ Some disadvantages of the file geodatabase format for preservation include following :
• An open specification has not been provided, as is the case for Shapefiles, and so there is no benefit from broad software support.
• As a collection of binary files of unknown construction, the file geodatabase cannot be inspected in the way a Personal Geodatabase can as an .mdb file
• The file geodatabase API, released in June 2011, arrived with a number of well-documented limitations, particularly with regard to various dataset types as well as most raster-related database components.
• The directory structure of the format requires that some care be used when transferring data. Databases may be corrupted if not transferred properly or files are renamed.
• Metadata is not externally accessible without using Esri's ArcCatalog software.