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Technology Overview
The Highest-Productivity
RAD Client/Server Tool for Windows
I. Executive Summary
II. Introduction
III. Business Insight: Turn data into actionable information for better decision making
A. Decision Cube Multi-Dimensional Analysis:
B. Integrated QuickReports -- faster and easier:
C. TeeCharts - integrated 3D charts:
IV. Active Insight -- An Enterprise Component Foundry for maximum reusability
A. One-Step ActiveX:
B. Built-in COM Support:
V. Code Insight: Comprehensive Coding Wizards for Ease of Use
A. Code Insight speeds the learning curve
Code Template Wizard for Correct Syntax
Code Completion Wizard for Simplified Programming
Code Parameter Wizard to Reduce Errors
ToolTip Expression Evaluation for Faster Debugging
DLL Debugging for Robust Code
VI. Multi-Tier Broker Architecture for scalability
A. Remote Data Broker for thin client database applications:
B. Constraint Broker for data validation, consistency and integrity
C. Business Object Broker for FailOver Safety
D. Scalable Database Engine Support
VII. Packages: Leading Edge Compiler Technology
VIII. Web-Enabled Client/Server Applications
A. WEB Broker: Client and Server Web Applications
B. ActiveForms and Web Deployment
IX. Comprehensive Client and Server Functionalities
A. Data Module and Remote Data Module Objects
B. Scaleable Active Dictionary
C. Object Repository
D. Visual Form Inheritance and Form Linking
E. SQL Monitor
F. SQL Explorer
G. InterBase NT - Relational Database
X. Conclusion
Application
developers rely on Delphi Client/Server Suite for high-productivity,
high-performance, scalable, client/server rapid application development
tools. As corporate developers expand
their scope to include the Internet and internal corporate
'Intranets,'
Today,
over 600,000 copies of
NASA's Atlantis and
American Airlines automated Flight Department procedures to eliminate paper-based-information bottlenecks. The flight department built a system to track air crew qualification requirements, schedule training events, and generate comprehensive reports. By using Delphi to develop applications that access the SABRE system running on IBM mainframes using DB2, American Airlines Flight Department has been able to save the very high cost of developing for SABREs Transaction Processing Facility (TPF) environment.
Other companies using Delphi Client/Server Suite to solve their business problems include: American Cyanamid, American Stores, Arthur Anderson, AT&T, BMW, BP Shipping, Bank of America, BBC Television, British Telecom, Compaq, DHL, EDS, Fiat, First National Bank of Chicago, Glaxo, KPMG, Sarah Lee Knitting, Standard & Poors, SwissBank, Union Bank, US Marine Corps, etc.
Making Multi-Tier Easier for Scalability and Reliability
Internet Enabling your
Client/Server Applications using your existing
Ease of Use and Highest
Productivity for the Business,
For many applications, particularly in the enterprise area, a more advanced, multi-tiered architecture has additional advantages in scalability, security and reliability. Coupled with the ongoing growth of corporate Intranets, we saw a natural convergence of client/server and Internet computing to deliver a mature, enterprise architecture that provides distributed computing capabilities without sacrificing the productivity and maturity of tools that exist in the client/server arena.
Delphi,
in it's third release, is an established development tool delivering depth so
that you can complete the most complex applications quickly, and breadth in
order to deliver two tier or multi-tier applications for the Internet and
Delphi Client/Server Suite is used to create departmental and corporate client/server applications with native database drivers for Oracle, Sybase, Informix, DB2, MS SQL Server and InterBase.
Delphi/400 Client/Server Suite,
scheduled for release in early 1997, gives midrange system developers the
productivity and performance of
Delphi Enterprise, for high-end
corporate developers, will combine
Business Insight turns data into actionable information for better decision making
Active Insight is an enterprise component foundry for reusability
Code Insight for ease of use and greater productivity
Multi-Tier Broker technologies reduce configuration and distribution costs with ultra-thin client database applications in a business-critical environment.
Remote Data Broker for zero configuration multi-tier applications
Business Broker for failover safety in a business critical application environment
Constraint Broker for data integrity and reduced network traffic
Web
Enabled Client/Server technologies allow you to deliver information over the
web using your existing
Web Broker and Web Deployment for high speed dissemination of information over the Web
This paper will discuss these technologies and how they enable a corporation to put the important aspects of the business at the center of development. By doing so, you can bring development projects to completion more quickly and scale with the growing demands of the business.
Corporations generate a lot of data and most business applications generate large volumes of transactional data. Consider an order entry system that records all the information about your customers. But increasingly what is needed is a way to take the large volumes of data and turn it into useful information to support better decision making. Taking advantage of this growing quantity of data can provide the insight into more cost-efficient business practices, insight into a competitive advantages or insight into market opportunities.
Decision Cube for multi-dimensional data analysis
TeeCharts for flexible high-speed visualization of database information
Quick Reports for summarization of data.
Each
component of
Decision Cube is for anyone who wants more sophisticated 'live' analysis of data. It allows for ad hoc data analysis, and yet scales to meet the high-level information delivery needs of executive users. Decision Cube can be delivered in a customized application or a web browser so that everyone has access to information.
'People want a tool that, like a spreadsheet, allows them to flip information and to focus on aspects of the business, modeling on what's important to them,' says Gord Patton 'For many companies, the data is too big and they need something to turn it into information.' Nadile, Lisa, Data Browsing, Information Week, Nov 4, 1997.
Decision Cube's advanced features like, Drill Down, Pivot and Aggregation go beyond static grids or DataWindows to provide new decision support mechanisms. This means visualizing data in new ways and making better decisions. Collapsible summaries and a drag and drop interface integrate seamlessly with graphs to drive your business.
Figure The Business Insight Decision Cube and integrated 3D charts supports multi-dimensional analysis for better decision making.
Decision
Cube is a complete set of visual components that can be visually
customized. You can tap the full power
of Decision Support analysis from the
High-Speed, easy-to-use and powerful reporting are important for effective communication of data through-out the enterprise. Now, Quick Reports allows rapid development of complex reports for distribution over the Web or from within an application to disseminate information more effectively.
QuickReports
is an integrated set of
Figure Business Insight includes seamlessly integrated QuickReports for rapid distribution of complex reports over the web or within an application.
Additionally, Quick Reports seamlessly integrates with TeeCharts to enhance your reports with sophisticated graphing capabilities and to give you insight into your business. Its unique multi-threaded architecture gives you added performance and flexibility to preview or print.
Quick Reports has been enhanced with an even easier, more intuitive and faster interface as well as many wizards to make it the easiest to use and most powerful report writer. For example, the new Report Wizard walks you through building simple, master-detail or label reports and the advanced expression evaluation wizard allows you to incorporate calculated fields with point and click ease.
Visualizing
data is the two-way visual and interactive interface between people and their
information resources. Comprehending
large quantities of data in order to make business decisions is vital to the
success of the organization. Business Insight - TeeCharts makes data patterns
evident and brings data relationships into focus. Visualizing data as graphs
with TeeCharts makes this easy. TeeCharts combines the speed of native
TeeCharts are easy to use and easy to learn. Developers work with a Wizard to graphically display enterprise or Internet data with over eleven different styles. For example Line, Bar, Polar, Candle and other chart styles makes interpreting data faster which leads to better and faster decision making.
Figure Business Insight Easy to use TeeCharts provides over eleven different graphing styles to turn data into information
TeeCharts are object-oriented graphing controls that provide you with a framework to develop custom business applications. From large complex analyses to full drill-down capabilities, TeeCharts applications enable you to understand large volumes of static and real-time information lending insight into the decision making process.
Today, over 60% of
'[Delphi 3] includes an 'enterprise component foundry' that leverages ActiveX technology to build distributed applicationsCreating components, such as ActiveX controls, DLLs (dynamic link libraries), and Web-based Active Documents is now a one-step process, according to beta testers. 'It used to be a code-intensive process. Now, it's painless, and the components are native to Windows 95 or Windows NT, or Internet Explorer, so they don't require a run-time interpreter,. Levin, Rich, Information Week, November 1996
Development teams within a
corporation use a variety of tools depending on their needs. They may use C++
Builder for power and control, or they may use
Figure 4.
Because
type
TCommandButton = class(TSpeedButton)
private
FCommand: string;
public
Procedure Click; override;
published
Property Command: string read FCommand write FCommand;
end;
implementation
Procedure TCommandButton.Click;
begin
WinExec(PChar(FCommand), SW_SHOW);
end;
end.
After creating this new Component, the One-Step ActiveX Control Wizard automatically generates all the ActiveX Code, a Type Library and Property page for immediate use within almost any Windows development tool or application.
Only
COM and Distributed COM (DCOM) are
critical architectures for multi-tier client and server applications. The new
COM classes in
Figure 5.
COM interfaces are automatically
garbage collected so that applications
free all their memory requirements. This
in turn increases application stability and automatically reduces the
possibility of errors. Every COM interface in
Remembering
the syntax of a statement; the methods, properties and events of a component;
or the declarations in a procedure will no longer be a concern for
Figure Code
Insight technologies increase developer productivity as well as making
Code
Template Wizard:
Code
Completion Wizard:
Code Parameter Wizard: The parameters for procedures, functions, methods, and events are now displayed in a Windows ToolTip as you code. Save valuable time by not having to navigate in the editor to where the declaration was first introduced. This reduces errors by making sure the parameters are passed in the correct order of the declaration
Tool Tip Expression Evaluation: The ToolTip expression evaluator allows the programmer to position the cursor over an object, variable, parameter, constant, or any other expression and see the assigned value in a Windows Tool Tip. This saves development time and gets robust applications to market more quickly.
DLL Debugging for
robust code: Delphi 3 makes
debugging even the most complex applications easier by allowing the developer
to debug DLLs within the
'Multi-tier architectures are characterized by the separation of the user interface, business logic and data access logic. Many organizations are implementing multi-tier architectures for enterprise applications to realize the two key benefits.
Multi-tier architecture allows for business rules to be centrally located on a shared server, providing the potential for reusability.
Secondly, centrally locating business rules makes maintenance much
easier and more cost effective. No
longer does software need to be propagated out to every client workstation each
time a business rule is changed.' Overstreet, Chip,
Figure 7. Delphi 3 makes Multi-Tier development easy with new Broker Technologies
Currently RPC Servers and DCOM Objects are incapable of retaining the notion of data in a multi-tier development environment. Programmers spend valuable time encoding and decoding data for transmittal to and from the server and client. Programmers spend valuable time and resources displaying data and tracking user actions on the data (e.g. Inserts, modifies and deletes). With respect to performance, as well as client and server side data caching, etc., programmers concern themselves with reducing network bandwidth
Unique to
Thin Client Configuration reduces maintenance costs: The architecture of the Remote Data Broker is such that it is no longer necessary to distribute and configure the Borland Database Engine on each client machine. Each client machine is enabled to communicate data to and from a Borland Database Engine or RPC Service on a centralized server. The Database Engine is centrally maintained and configured only once at the server instead of on every client. This significantly reduces maintenance and cost. No other rapid application development tool allows you to create zero configuration database applications
Centralized connection management reduces simultaneous database access fees: Because all connections to the database are centrally managed, the number of simultaneous connections to your data can be managed and reduced resulting in even further cost savings.
Briefcase database applications enable remote users: The client
application can use all of
For example, Sales Force automation applications typically need to download pertinent contact information, product inventories, and price data to the sales representative for use while he or she is on the road. The user modifies and inserts data as they conduct business just as if they were connected at the office. The salesperson is now able to respond to their customers more quickly and more responsively with more accurate information. After their business trip is concluded, they send the new orders to the server for consolidation with the centralized database for further processing.
To write a Sales Force automation
application in today's development tools would require very large amounts of
code. Great expertise about networks,
database systems, configurations and leading edge client/server techniques
would have to be learned and used to achieve this task. With
Efficient use of the Network increases performance: The Remote Data Broker intelligently uses the network by giving the developer the ability to request only the data the application needs. The DataPackets sent to and from the client and server are optimized to send data, data validation rules and meta-data so that the client application is no longer dependent on network or the server. The developer is given further control to request a full result set or partial result sets. Only the modifications made to the data at the client are sent back to the server, not the entire result set. Smaller movements of data from client to server significantly reduce costly network bandwidth.
Transaction resolution closely coupled to reusable business rules for better efficiencies: Modifications to data at the client are automatically identified and maintained for processing at the server. The Borland Database Engine, centrally located on an application server, will automatically trap errors that occur due to transaction latencies, changed data values, invalid data, or other database server failures. It then reports back to the application server the exact nature of the problem. The developer can then resolve the transaction failures with predefined business rules on the server or send the appropriate error messages back to the client for further resolution. Centrally maintaining the database transactions and coupling them with centralized business rules helps more efficiently manage the business.
Figure 8. Only
Remote Data Broker Objects can maintained by the Business Object Broker
for failover safety. The Remote Data
Broker uses full object-orientation to create COM Objects or use RPC
Services. To maintain these distributed
objects in a business critical application, they have to be managed. With the Business Object Broker,
Data validation and consistency are important to maintaining data integrity. Currently data integrity is maintained by a set of checks, constraints and validation rules applied at the client application, the database server or in a business rule in a multi-tier environment. Each location option has advantages and disadvantages.
Client: Validation rules applied at the client reduce network traffic because you don't have to go over the network to the server to see if the data is valid. However, client side validation requires costly maintenance as the rules are distributed among many clients.
Server: On the other hand, database server validations are centrally enforced, easily modified and applied automatically to all applications using the database server. However, server side validation requires that the client send all data over the network to the server for validation. This makes the application unresponsive to the user and costly in network bandwidth.
Business Rules: Business Rule validations have the advantage of being centrally maintained, easily changed, and more easily written than in RDBMs proprietary languages, but they still require network traffic. Many of these rules will duplicate complement the rules being applied at the database server instead of replace them.
Only
As
the users of an application modify data, they are informed of invalid input
with developer defined Custom Error Messages for quicker resolution.
Figure Exclusive to
Business critical applications need to be reliable and fast. In order to achieve this, developers can partition applications so that they provide redundancy to their business rules systems. Also, developers can dedicate high-speed resources to the processor intensive business rules in the application. Additionally, separating the business rules from both the database and the user interface enhances the reusability of business components from application to application.
Figure 10.
With the Entera AppMinder product, the developer can not only check for availability of an object on a server, but can poll for machine loads and then balance the system for optimum performance.
The Business Object Broker takes
advantage of the true object-oriented nature of
SQL Link native drivers provide the fastest way to connect to database servers by writing directly to Database Client Services. Delphi Client / Server Suite 3 incorporates new 32 bit high speed native drivers that offer even faster performance and more functionality. These drivers include: DB2, Informix, Oracle, Sybase, MS SQL Server, AS400, and InterBase The new SQL Links enables tools such as the SQL Monitor and SQL Explorer to assist the developer in creating and tuning applications.
Delphi 3 uses an open and scalable DataSet architecture in order to support multiple database engines. The developer is given complete control to provide the essential database services (e.g. caching, retrieval, language collating, heterogeneous access, generic cursor support) necessary for a specific application. Different database engines now have a formal way to produce result sets that work seamlessly with the over 20 powerful database visualization controls found in Delphi.
Figure 11. Delphi 3's open database architecture supports multiple database engines to leverage over twelve data-aware components.
The new virtualized TDataSet easily allows programmers to bind new data sources into the Delphi environment. This architecture is used to provide complete integration with Entera for integration with RPC database server objects. In a multi-tier environment, data sets can be provided by RPCs, or COM objects and in the future CORBA objects. The Entera Database Server Generator has the ability to develop and deploy database servers/objects for Oracle, Informix, DB2, Sybase, SQL Server, IMS, VSAM, or any other database that supports ODBC. By binding these objects into the virtualized TDataSet, the developer can create applications that use legacy-database systems along side existing applications
Packages are a unique leading-edge compiler technology that gives developers the ability to breakdown applications into separate, reusable compiled pieces without a slowdown in performance.
Packages turn the Delphi Visual Component Library, your own set of components, or any Delphi unit into a specialized Package DLL. Delphi 3 Packages, VCL30 and VCLDB30, encapsulate the entire component library so that programs no longer have to link the components into each executable. Encapsulation significantly reduces the size of executables, for example a 500K executable could easily become 15K. In turn, these executables are more easily distributed over the web and more easily configured on the client machine.
Using Packages requires no changes to the rapid application development within Delphi or to the construction of a Delphi project. Delphi offers the flexibility to use or not to use packages, depending on the requirements of application delivery and the overall goals of the organization.
Packages are accompanied by a supplementary DCP file that enables object-oriented class manipulations, such as Inheritance, Polymorphism, and Encapsulation, across DLL boundaries for maximum reusability.
Figure 12. Packages significantly reduce the size of executables for easy web deployment
Because the Visual Component Library also consists of packages, they can be configured to be used on a per project basis, thereby reducing the complexity of the environment and the associated learning curves. Packages increase the capabilities for team development by segregating the Delphi VCL from the business components developed in the corporation. The business components can be maintained discretely, versioned, easily updated, and quickly incorporated into new projects.
Conclusion: Only Delphi 3 Packaged applications are easily distributed and configured for a thin client multi-tier architecture without runtime interpreter DLLs.
Delphi provides two mechanism to Web-Enable your client/server applications while using your existing Delphi skills.
WEB Broker for high speed dissemination of database information over the web. The Web Broker makes it easy to deliver database information as HTML to any browser on any platform.
ActiveForms & Active Web Deployment for zero-configuration, client/server applications. ActiveForms and Active Web Deployment use the web infrastructure to deliver ultra-thin client/server applications.
Client/Server and Internet development benefit from high speed native code compilers, reusable componentry, scalable databases, multi-tier architecture and rapid application development to deliver an advantage in a dynamic business environment.
'Movement [of data and applications], componentry and distribution are all coming together to redefine our systemsThe Web, combined with other critical innovative technologies such as replication, messaging, component architecture (for example OLE, CORBA, Java and so on), and N-Tier (distributed) application capabilities, will change the world's IS architectures to be distributed in design (both data and applications), dynamic in movement, and component-based.' Pantaja, Mary, Client/Server Redefined, Database Programming and Design, October 1996, Vol 9 Number 10.
Delphi 3 includes Web Broker technology that introduces high throughput and high speed, server side web development for creating, managing and delivering data over the web. Web Broker includes four server side components, the WebBridge, and WebModules. These technologies will be discussed in detail below.
Figure Delphi 3 provides client and server solutions for the web.
WebServer Applications -- Web enabling client/server applications:
Due to its open architecture and support of system DLLs, Delphi 3 is the only high-productivity rapid application development environment that lets you create high-speed, high-throughput web-delivered data applications using your existing client/server knowledge.
WebServer applications DLL or Executable extensions to the Web Server. Create ISAPI/NSAPI DLLs, server interfaces from Microsoft and Netscape respectively, or CGI or WinCGI applications. With WebServer applications, you have complete control over a web sub-site without worrying about resource management. Web Sever applications also bridge to the high-speed transaction, and multi-tier capabilities of Delphi 3 so that you can easily scale your web applications to the large number of clients and large quantities of data.
Figure The extensible Object Repository contains WebServer Applications for creating, managing, and delivering corporate data over the web.
WebBridge: The WebBridge allows developers to program to a common API for both the Microsoft and NetScape Web Server APIs, NSAPI and ISAPI, which protects your code base from emerging and competing Internet standards. The WebServer application automatically handles communication to ISAPI and NSAPI so that the developer is isolated from the idiosyncrasies of each system. The developer can then concentrate on implementing a business solution regardless of the back-end web server.
Figure Delphi 3's WEB Insight leverages existing knowledge of client/server application design for creating WebServer applications.
WebModules: The WebModule acts as your WebServer's application information center by providing a designated central location for dispatching requests, defining specific URI (Uniform Resource Indicator) actions, and creating HTML pages. It combines these web-specific actions with data access and business rules in order to deliver high through-put data over the web without effort. The WebModule is a codeless and visual way of providing control over multiple requests coming into a web sub-site in order to provide client/server and web functionality.
Sessions: The Session handles simultaneous database requests by automatically creating new Borland Database Engine segments for each request. Borland designed the Borland Database Engine to handle multiple users through a single instantiation. When the Microsoft Internet Information Server (IIS) or NetScape Server processes call into the Borland Database engine on behalf of a number of browser clients, sessions are automatically created. The WebSession reduces server memory footprint and speeds web server application development by reducing configuration issues.
Web Dispatcher: The Web Dispatcher is the centralized request processing center. It allows the Delphi developer to produce web content using the same skill sets used in creating Client/Server applications. The WebDispatcher prioritizes requests and then dispatches each request to specific responders. These responders produce HTML text for specific data types.
HTML Producers: Delphi includes three different HTML Producer objects. They turn database information or programmatic information into HTML for delivery by the WebBridge.
Conclusion: Delphi is the only high-productivity rapid application development environment that creates, manages, and delivers data over the web. Delphi gives the developer the power to produce web delivered database applications by creating machine code DLLs that bridge both Microsoft and Netscape Internet standards while using your existing Delphi skills. Delphi Web Server applications also bridge to Delphi's high-speed, multi-tier development environment to scale to large volumes of users and large quantities of data.
Delphi provides the easiest way to web-enable client/server applications that run on Windows Clients by turning any Delphi form into an ActiveForm. ActiveForms are ActiveX Controls that use the Delphi form as a container for other Delphi components. ActiveForms publish ActiveX property pages and type libraries for adding high-speed functionality to other development environments, for example Internet Explorer, Visual Basic or PowerBuilder. Or use these forms to deliver and configure applications over the Internet.
Figure Delphi uses the Web infrastructure for ActiveX delivery of ultra-thin, native code compiled client/server applications.
In combination, only Delphi's ActiveForms and Remote Data Broker help deliver ultra-thin, zero-configuration, multi-tier database application. Web Deployment automatically creates an HTML file that delivers an ActiveForm to the client along with all the files (packages, database files, etc.) necessary to run the application.
Figure Only Delphi 3's Web Deployment can deliver native code compiled, zero configuration ActiveForm client/server applications.
Support for web deployment is automatic and makes use of both Microsoft and Netscape browser support for CAB files. In addition, to facilitate efficient downloading, a single Delphi library or application can now be packaged into separate DLLs without compromising execution performance. Also, Code Signing is incorporated in order to enforce security. Using our standard VCL packages, a Delphi application or DCOM server can now be as small as 15K. When combined with Delphis new automatic web deployment support, an entire distributed application can be stored in a repository on a centralized server and deployed on multiple machines with a single click in a net browser. Each time the application is subsequently launched by a user, automatic version checking is performed and only those packages and components that have changed, if any, will be re-deployed. These high performance, native code applications can run in a browser or as standalone desktop applications.
No other development tool can take full advantage of the web while leveraging your client/server expertise.
Figure Delphi 3's creation of ActiveForms adds high-speed functionality to Internet Explorer, PowerBuilder, Microsoft Office and Visual Basic.
Delphi Client / Server Suite 3 includes an integrated suite of tools for building high performance Client / Server applications with such extensive features as:
Object Oriented Database Application Architecture
Flexible Client / Server transaction models.
Centralized Object Repository for team development
SQL Monitor for SQL Testing and Tuning
SQL Explorer for integrated administration of database servers
Data Module Objects for separating business logic from visual data representation
Scaleable Database Dictionary for consistent use of extended field attributes
The Data Module, Scaleable Database Dictionary and Object Repository are technologies that become the framework of a unique Database Application Architecture. This architecture then becomes the basis for building high performance Client / Server applications.
Delphi Client / Server Suite 3's Data Module and Remote DataModule Objects act as your applications information core by providing a designated central location for defining data access and business rules. The Data Module Object separates business logic from the GUI and acts as a codeless way to connect and manage business logic from a single location.
Figure Delphi Client / Server Suite 3's new Data Module and Remote Data Module Objects encapsulate Business Rules.
Business logic can be applied to Tables, Stored Procedures, Queries, and Providers by creating methods on Before and After events such as posts, deletes, inserts and edits. This allows you to create new business objects more easily.
Master Detail Data relationships are defined in a codeless manner in Delphi. The Developer can create Client / Server applications easily and quickly by visually setting properties on the Datasources or by using the Database Form Wizard.
Applications and forms can be visually linked to the Data Module to propagate business logic without writing extra code.
Data Modules are classes of objects that pertain to the interaction of data with the database server. Isolating all database operations in Client / Server application makes application maintenance simple.
The database dictionary stores and uses customized information about the contents of the data in your tables. The dictionary ties the familiar model of working with fields through the property inspector to a permanent storage facility. The data dictionary holds information about extended field attributes like min, max, default values, constraints, error messages and display preferences. Using the data dictionary has two advantages:
Consistency: common field attributes are centrally stored in the data dictionary and then retrieved at application design time. A developer can create extended field attribute domains and the team can appropriately apply them to fields.
Network Traffic Reduction: Delphi allows for data validation at the client or at the server. The data dictionary can maintain extended field attributes that perform client side data validation efficiently by reducing network traffic.
Figure The Scaleable Data Dictionary maintains consistency by storing attribute sets for Database Schema.
Delphi Client / Server Suite 3's Object Repository stores and manages application objects: Forms, Data Modules, Experts, and DLLs. In essence, it centrally locates corporate assets so that they may be leveraged by the team to eliminate redundant development efforts. As objects proliferate, the repository increases in importance.
The Object Repository:
Supports team development practices by referencing objects on a network.
Is customizable so that developers can define their own logical groupings of objects to facilitate reuse.
Figure Object Repository centrally locates application objects and enhances team development.
Developing a corporate standard in applications is important. Ensuring that these standards are adhered to is more difficult. Visual Form Inheritance and Form Linking extends object oriented programming to a visual paradigm ensuring that corporate and programmatic standards are maintained from project to project. In conjunction with the Object Repository, these standards are centrally managed resulting in faster project turn-around time.
Visual Form Inheritance allows anyone to take advantage of object-oriented reusability and maintainability by providing a codeless way to use inheritance, encapsulation and polymorphism.
Figure Visual Form Inheritance simplifies Object Oriented reusability.
Delphi Client / Server Suite 3 is the only RAD tool that integrates a native SQL monitor for testing, debugging and tuning SQL queries in Client / Server applications. This in turn increases developer productivity and application performance.
The SQL Monitor enables the developer to trace calls between the client and server. This information allows the developer to find problematic SQL statements and then optimize the SQL transactions. A series of trace options lets the developer customize the amount and type of information that is reported on. The SQL Monitor helps the developer know that the SQL in the application is being performed optimally, what is the SQL generated by the Borland Database Engine, if the Database Client Libraries are functioning properly, and if the database server is executing a run-away query. The additional capabilities to save and print the session log enables more thorough testing.
Figure Delphi Client / Server Suite 3 is the only RAD tool that integrates a native SQL monitor for testing, debugging and tuning SQL in Client / Server applications.
The SQL Explorer provides the information center for your database management demands; it supports the creation and modification of tables, aliases, stored procedures, triggers and business rules through interactive SQL. This graphical tool is an integrated database schema and content management utility tailored to the needs of professional database developers.
The SQL Explorer, unique to Delphi, makes database administration easier and more intuitive than having to use a separate non-integrated tool. A simple to use graphical interface is a perfect way to represent the complex relationships that exist in a database server. The SQL Explorer presents schema information from Oracle, Sybase, InterBase, Informix, DB2, MS SQL Server and others. The developer can drag and drop fields, tables, and stored procedures onto the Delphi application form to build Client / Server database applications quickly. The developer can also issue SQL statements directed to multiple servers and multiple databases.
Figure The SQL Explorer is an integrated tool for administering SQL and PC Databases from within the Delphi Client / Server Suite 3 environment.
The SQL Explorer, also manages the Scaleable Database Dictionary. The simple to use interface enables the developer to easily define new domains of extended field attributes and then associate those to a field. The next time the field is used in an application, all the attributes are automatically applied.
Delphi Client / Server Suite 3 includes a four user InterBase NT developer license. Developers can create standalone client / server applications using a scaleable relational database. When the volume of data, or size of application grows, both the InterBase relational database and the Delphi application will scale accordingly.
InterBase is Borlands high performance, cross platform SQL Server. InterBase is available on over 15 operating systems, including: Windows 3.1, Windows 95, Windows NT, NetWare, SCO, Sun OS, Sun Solaris, HP-UX, IBM AIX, SGI IRIX, etc. InterBase is ANSI SQL 92 entry level conformant, supports server events for event driven programming, and has an exceptional concurrency model for multiuser access. InterBase offers record level locking and due to its Multi-Generational Architecture delivers superior performance because database read operations do not block database write operations.
Local InterBase, also available in Client / Server Suite 3, provides Delphi developers with their own single user ANSI 92 SQL conformant server for prototyping and development of true client/server applications on Windows 95 or Windows NT. Local InterBase has all of the same functionality as the multiuser versions of InterBase available for NT and Unix, including transaction control, stored procedures, triggers, and even event alerters, which enable event driven programming. This means that development can occur on a laptop while on the train, airplane, or at the customer site, and that the final database to be used can be changed when the application is ready to be deployed.
Using Delphi Client/Server Suite 3, developers can design, prototype, and test their Delphi/InterBase applications on one machine. InterBase offers an exceptional Windows 95 GUI interface including configurable property sheets, native 32 bit tools like the Server Manager and Interactive SQL tools, and the complete documentation in Windows 95 Help.
InterBase ensure that data is always available due to their excellent multiuser performance, high security, and fast recovery features. InterBase is used in the aeronautical industries by companies like Boeing and Lockheed for manufacturing, by the Money Store and many other banking institutions, and in financial trading centers like the Philadelphia, Boston, and Russian Stock Exchanges. The common thread among all these customers is the need for excellent multiuser performance, high security, and fast recovery when system failures occur.
Borland has a comprehensive family of client/server and Internet development tools that offer developers the competitive advantage of an open, scalable architecture with high-performance and high-productivity. Within the family of tools, Delphi 3 is the highest productivity RAD client/server tool for Windows that seamlessly scales from the desktop to the enterprise.
By sharing common technologies across our product lines, Borland is able to deliver tools that are easy to learn and leverage your investment in training and code. For example, all of the Borland development tools are available in client/server versions which include high-performance SQL Links native drivers for connecting to corporate databases including Oracle, Sybase, Informix, Microsoft SQL Server, DB2 and InterBase as well as ODBC.
Shared technologies: Borland shared technologies reduce your development costs.
Common RAD WorkBench
Consistent, open development environments
Reusable component architectures and component libraries
High-performance native drivers to corporate databases
Advanced SQL tools for database management and performance monitoring
Award-winning debugger technology
Open, scalable architecture with Entera intelligent middleware
As application complexity has increased due to the demands of the enterprise and the Internet, Delphi has added significant functionality for a smooth transition. The Data Broker, Packages, OLEnterprise, Business Broker and Internet Enablement in Delphi 3 allow for thin client applications to be easily distributed, configured, and maintained, thereby reducing costs. Built in COM and ActiveX support allow for language interoperability so that you can leverage your existing investments. Access to Entera and the high-speed native SQL Links drivers allow you to integrate legacy data so that the company's knowledge base can be fully utilized. Open support for industry standards provides directory and security services crucial to business-critical applications. Delphi is the only scalable and open, multi-tier architecture that puts your business at the center of development.
Delphi continues to set the standard for high productivity and rapid development of high-performance client, server and multi-tier applications through the enterprise and across the Internet.
[LD1]The inherent model for components in Delphi is the optimized Visual Component Library which get compiled into an executable to produces the fastest client/server applications. Delphi developers have the option of implementing interfaces on existing Delphi classes, thereby incurring the overhead of interfaces only when necessary.
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