Automate Your GIS Application: Initiate | Innovate | Automate

Adding PDF Icon to Links

First Place an icon file in images folder, then put the following code in <head> tag


<script src=”http://jqueryjs.googlecode.com/files/jquery-1.3.2.min.js”></script>

<script type=”text/javascript”>

$(document).ready(function() {

$(’a[href^=mailto:]‘).addClass(’mailto’);

$(’a[href$=.pdf]‘).addClass(’pdflink’);

$(’a[href^=http][href*=henry]‘).addClass(’henrylink’);

});

</script>

<style>

.mailto {

background: url(images/mail.png) no-repeat right top;

padding-right: 18px;

}

.pdflink {

background: url(images/pdf_button.png) no-repeat right top;

padding-right: 18px;

}

</style>

Autodesk Topobase

Check the following video for Autodesk Topobase.

Video

Oracle Overview

In this section we will examine Oracle database, how this product can be suitable for our GIS projects.
Oracle products are extraordinarily careful with data: For safety, they write all changes to data in two separate places—first to a transaction log and then to the database data file. Support transactions, which guarantees that if a mistake or an error happens as part of a series of related database commands, every related change will be undone in reverse order (an action called a rollback) to preserve database integrity.
Extensive SQL support, transaction support, and scalability are three key features that distinguish Oracle from other products which are adequate for desktop work, such as Microsoft Access.
Elements that are important when you’re choosing database server software for mission-critical projects are…..
Support for security, backup management, replication, programmability, extensibility, fault tolerance, and manageability.
A commitment to open-source standards like Java and XML is another trend. Oracle has all added extensive Java features to its databases…
This move was realized by Microsoft, which was the first to include features for data warehousing and data analysis (also called online analytical processing, or OLAP) into its database, starting with SQL Server 7.0. Oracle and IBM later did the same.The latest innovation—offered in Oracle9i—is integrated data mining, which helps business people do advanced data analysis.
A commitment to open-source standards like Java and XML is another trend. Oracle has all added extensive Java features to its databases.
Most database servers are on a collision course with XML. The move to XML is a natural tie-in with a new approach to computing—deploying database-enabled Web applications running on application servers in place of standalone Windows programs. XML is causing database vendors to rethink their direction from the ground up, and the SQL language itself could well be on the way out in a few years, potentially to be replaced by an XML-based language called XML Query, now in development.
Clustering several database servers for increased speed and reliability is another significant development and was a major focus of the Oracle9i launch. Organizations that can tolerate database downtimes of only seconds per year can turn to clustering.
As well as considering cost, capabilities, and speed, keep in mind the need for specially trained staff to manage your database system. A pro at operating systems and network hardware who wings it on database design and index layout will probably create something that works fine for 1 user but totally melts with 100 users.

Pragmatic

Oracle has taken a pragmatic approach to delivering object functionality in the server. We deliver the needed functionality in phases, addressing the most important and clearly understood customer needs first, while giving customers sufficient time to absorb and effectively use the advances in the server. As a result, with Oracle9i, users can store business objects or multimedia data in the server, run Java objects in the server, and also easily extend the database for new kinds of data. In subsequent releases, we will carefully phase in features, such as inheritance. Our basic goal is to ensure operational viability and mission-critical readiness. To this end, we have eschewed an en masse addition of new features.

Comprehensive
In bringing object technology to the mainstream market, Oracle has adopted a comprehensive, company-wide effort for integrating the features in the Oracle9i server with application development products and tools. Various language interfaces (such as the SQL, PL/SQL™, Java (JDBC and SQLJ), the Oracle Precompilers™ and Oracle Objects for OLE™) all support objects. Oracle Designer™ and Oracle Developer™ provide tool-support for objects.
Oracle9i is functionally rich, containing a number of important technological advances, such as object types, object IDs, object views, an object cache, and Java in the database. These bring object technology to the mainstream market and are discussed in more detail in the next section.

Oracle 9i Solution
Having identified the kinds of business needs that Oracle aimed to solve and the strategy it adopted to solve them, this section follows with a description of the fundamental technical components of Oracle9i’s object functionality

Integrated

Oracle has chosen to offer a tightly integrated object solution with Oracle9i. Object technology permeates the Oracle9i server and is not offered as a thin veneer on top of an existing relational database. Oracle9i is an integrated product in three important ways:
It has a single architecture for both objects and relational data.
The object technology is combined with the latest advances in functionality for data warehousing and OLTP, such as partitioning and parallel queries.
It has consistent, interchangeable interfaces for accessing both relational data and objects (such as SQL, the Oracle Call Interface, Pro*C, SQLJ, JDBC, Oracle Objects for OLE, and so on).

Evolutionary

With Oracle9i, Oracle is bringing the next generation of relational database technology to the mainstream market, by providing users the ability to define and store business objects in the database, and by extending support for rich, multimedia datatypes. Oracle9i integrates object data and relational data, allowing customers to treat object data as relations and also relational data as objects. For example, Oracle allows users to use SQL to access objects and to use object views to compose objects from relational data. New features designed for use with objects, such as fully updatable views, can be used with relational tables. Oracle9i does not require users to migrate any of their existing Oracle7 applications. This creates a smooth evolutionary path that allows object types and relational tables to coexist in the same database, and existing Oracle7 applications and tools to coexist with Oracle9i applications. It leverages existing investments in four important ways:
It integrates relational data with objects in the same data store.
It exploits proven Oracle technology to provide customers with a robust, scalable deployment platform.
It allows customers to use their huge base of existing applications, without needing to migrate them.
It leverages customers’ knowledge of existing application development products and tools.

Oracle Database

Oracle’s family of industry-leading database, networking and gateway products enable corporations to access any data, on any server, over any network, from any client device.
The Oracle Database has been designed for the emerging hosted application market on the internet. With transparent, rapid-growth clustering capabilities, powerful and cost effective security measures, zero-data-loss safeguards and real-time intelligence, Oracle DB is a complete and simple software infrastructure for the internet’s next generation.
The Oracle9i Database Server was designed to consolidate data or Internet Content from many specialized data sources. Through a comprehensive data extensibility architecture, the Oracle Database provides facilities to efficiently store, manage, index, search and access large volumes of:
Structured Data modelled either as Relational structures or Object-relational structures (object types and collections) including those with inheritance.
Data in Large Objects (LOBs) which can be either BLOBs, CLOBs, NCLOBs, or BFILEs. Multimedia Data consisting of Text, Image, Audio, Video, or Spatial data.
Files through the Internet File System which allows any file to be stored and managed in the Oracle Database; and XML Data through support of the new XMLType which allows both structured and unstructured XML Data and Documents to be stored, managed, and accessed efficiently.
Specialized Data consisting of e-mail, Unified Messaging, Enterprise Messaging, and LDAP Directory Data.
In addition, these different kinds of data are simply treated as different datatypes within the Oracle Database and, as a result, it is very easy to combine these different types of data within a single SQL query expression or an application.
Besides, the Oracle9i is an object-relational database and it provides the most complete solution for addressing the object functionality needs of the mainstream business market.
It enables the management of complex Java or multimedia data in developing applications for the Internet.
It provides support for the graph- or tree-structured C++ and Java data encountered in vertical industry applications, such as in telecommunications, energy, and finance.
It facilitates flexible, maintainable code for traditional database applications.
It enables the database to be customized for specific application domains.
Combining these capabilities in a single data store, which is also the industry’s highest performing, most robust and scalable deployment platform, the Oracle9i object-relational technology defines the next generation of databases.
Databases have four fundamental requirements:
Modelling Business Processes Better
Businesses constantly search for ways to manage the complexity of modelling their complicated and constantly changing processes. The model must be flexible and capable of supporting complexity. Applications need to be able to treat these business abstractions in the same way across all tiers of a IT infrastructure, as complete entities, whether they reside in the database or manipulated outside of it.
This requires the database to:
Allow the native representation of complex business objects in the database.
Provide ways to query over these objects.
Provide mechanisms for the database to seamlessly map the stored business objects to client-side applications or mid-tier servers.
Allow access to business objects from multiple languages and interfaces.
Integrating All Data in a Single Store
Early information systems dealt with simple, structured data. Gradually, the ability to model the real world better has led to a progressive growth of data-complexity in such systems. It has become clear that the prevailing technologies are no longer universally adequate to handle the complex, content-rich data that applications demand. In industry, the answer has been to use the basic constructs of object technology to rapidly standardize on complex data models.
The Internet has brought a new infrastructure over which rich, multimedia information can be easily exchanged. Users demand a richer semantic from applications. People want to deal with images and HTML, not characters and lines. As businesses rise to exploit the Web, they are looking for new ways to combine rich, unstructured multimedia information with their business information. Finally, a number of new initiatives, such as a standard Extensible Markup Language (XML), are being pursued in the World Wide Web Consortium. These bring yet another kind of data into play – semi structured data whose format is not known a priori, but deduced from the data itself. To facilitate all these applications, the database must provide a single store where customers can store and query on all the various kinds of data they use to compose their business objects. These objects include structured data (simple or complex), unstructured rich multimedia data, as well as the semi-structured data arising from XML, or other interchange formats.
Leveraging The Web
In order that databases continue to seamlessly serve thousands of intranet/internet users, it is imperative that there be native support in the database for Web technologies. The database must provide support for Java, and Java objects must be seamlessly represented in the database. There must be support for storing retrieving data in popular Web formats such as HTML and XML.
Exploiting Extensible, Component-Based Architectures
Corporate intranets and the public Internet are rapidly becoming the deployment environments for many mission-critical applications. Spurred by the escalating cost of building systems from scratch, and the simultaneous proliferation of public component-based standards, such as Enterprise JavaBeans (EJBs) and the Common Object Request Broker Architecture (CORBA), corporations now find it feasible to build applications by assembling prefabricated components. Component technology rests on the notion of reusable objects, and it is imperative that all the tiers of an enterprise architecture leverage the advantages of object technology. The database infrastructure must allow the plugging-in of modular components, to easily extend itself to new requirements and new data.
Using New Technology to Evolve Existing Applications
To protect and leverage customers’ existing investments in technology, their existing relational databases must be enriched with object technology. In evolving their relational databases, customers must be provided with a smooth evolutionary path that meets three requirements:
It must allow users to leverage their knowledge of existing products.
It must provide predictable performance, scalability, reliability, and manageability.
It must conform to open industry standards.
Oracle9i’s ‘objects and extensibility’ technology meets all these new requirements on databases. Let us look more closely at Oracle’s approach.

Defining Oracle’s Approach

The object-relational technology in 9i has five basic design guidelines. It has to be:

  • Evolutionary
  • Integrated
  • Pragmatic
  • Open
  • Comprehensive

Database Management Systems: Review in the context of GIS Applications

In this section we will examine Oracle database, how this product can be suitable for our GIS projects.
Oracle products are extraordinarily careful with data: For safety, they write all changes to data in two separate places—first to a transaction log and then to the database data file. Support transactions, which guarantees that if a mistake or an error happens as part of a series of related database commands, every related change will be undone in reverse order (an action called a rollback) to preserve database integrity.
Extensive SQL support, transaction support, and scalability are three key features that distinguish Oracle from other products which are adequate for desktop work, such as Microsoft Access.
Elements that are important when you’re choosing database server software for mission-critical projects are…..
Support for security, backup management, replication, programmability, extensibility, fault tolerance, and manageability.
A commitment to open-source standards like Java and XML is another trend. Oracle has all added extensive Java features to its databases…

Models for storing and representing spatial data in a GIS system

There are two main models for storing and representing spatial data in a Geographic Information System (GIS): the raster the vector models:

Raster Data – raster (or grid cell type) data can be used for analyzing, overlaying, and modelling area features such as soil types or forested areas. Raster data are generally typically scanned in from maps.
Vector Data – vector data can be used to represent linear features such as roads, streams or area edges and can be combined with raster data for display purposes or for analysis.
In general, Raster maps are faster, Vector maps are more specific and more accurate.

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Open-Source GIS — Free GIS softwares available

Open-source GIS packages can be provided at no cost but usually more effort is required for the installation and for the development of customized applications related to commercial GIS. Moreover documentation and user support is not enough.
MAPSERVER and GRASS GIS are selected among the existing open-source GIS tools to be presented in the current report as most appropriate for your GIS requirements.
Mapserver is not a complete GIS but has many interesting features for your applications and a relatively good level of documentation and WEB-site support.
Additionally a module for PDA’s has been developed recently in the frame of an IST project.
GRASS is a full-featured open source GIS which can support sophisticated spatial analysis and can be customized for the purposes of your applications.

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