1.Explain coldfusion architecture?

ColdFusion is a rapid application development environment that lets you build dynamic websites and Internet applications quickly and easily.

ColdFusion consists of the following core elements:

• CFScript Engine
• CFML
• ColdFusion Administrator
• Verity Search Engine
• Extensions

• CFScript Engine
  Coldfusion includes a built-in scripting language, CFScript, that let us write code in a JavaScript fashion.


• ColdFusion Markup Language
  ColdFusion Markup Language (CFML) is a tag-based language, similar to HTML, that uses special tags and Functions.


• Coldfusion Administrator
  ColdFusion Administrator configures and manages the ColdFusion application server. It is a secure web-based application like control panel that you can access using any web browser, from any computer with an Internet connection.


• Verity search Engine -
  The Verity Search Server (also called the Verity search engine) provides full text search capability for documents and data on a ColdFusion site.


• Extension
  We can extend CFML further by creating custom tags or user-defined functions (UDFs), or by integrating COM,C++, and Java objects by using CFX tag.

2.How coldfusion process the request?

• A web browser makes a request to a web server for a template with a .cfm extension.
• The web server receives the request and forwards it to the ColdFusion Application Server.
• The ColdFusion Application Server parses the CFML template and processes the tags and functions accordingly, interacting with other services, such as data sources or mail servers, directory, file servers, report servers etc.
• The ColdFusion Application Server combines its dynamic output with the static HTML (and JavaScript or VB Script, if any) in the template and passes the whole page back to the web server.
• The web server passes the dynamically generated content back to the client machine’s web browser.

3.What is Application.cfm?

When ColdFusion receives a request for an application page, it searches the pages directory for a file named Application.cfm. If not exists, the Application.cfm code is logically included at the beginning of that application page.
If your application runs on a UNIX platform, which is case-sensitive, you must spell Application.cfm with an initial capital letter.

4.What is Web Server?

A computer that delivers (serves up) Web pages. Every Web server has an IP address and possibly a domain name. For example, if you enter the URL http://www.domainname.com/index.html in your browser, this sends a request to the server whose domain name is domainname.com. The server then fetches the page named index.html and sends it to your browser.
Any computer can be turned into a Web server by installing server software and connecting the machine to the Internet. There are many Web server software applications, including public domain software from NCSA and Apache, and commercial packages from Microsoft, Netscape and others.

5.What is Application Server?

A server that exposes business logic to client applications through various protocols including HTTP, HTTPS, IIOS/SSL. Eg: Sun Java Application server, weblogic server
It takes care of important issues like Transaction Management, Security, Database Connection Pooling, Clustering, Scalability,session management,load balancing,thread management and Messaging etc. A web server cannot provide these.

6.How can you communicate with web server (Apache or IIS) from Coldfusion?

Cold Fusion is an example of a Common Gateway Interface application. The Common Gateway Interface is a mechanism to allow Web servers, which are designed to serve static documents, to receive dynamic output from programs and serve it as if it were static data.

• When a browser sends a request for a Cold Fusion template to a Web server, several things must happen. First, the Web server recognizes the information from the browser as a request for CGI output.
• If the request was initiated from a form, the server has to write the form field information to some area in storage that is accessible to other programs on the machine. Usually, this is done by using STDOUT data streams. The WinCGI interface, which can be used by WebSite and other servers, writes the form data to INI-style files on disk, which are then opened and read by the CGI application.
• The CGI program requests data from the data source, which is returned in step
• The CGI program formats the data as HTML output, returning this output to the server in step
• The server receives this output, performs any further server-side processing necessary, and then sends it to the browser.

7.What are the advantages of Cold fusion?

Simplified Installation and Migration
All Operating System (OS) Support
All Database support
Faster Development & Easy to Learn
Improved & support for all Protocols
access to all the J2EE libraries
Integration with Other adobe Products (Flex, Flash, PDF..)

8.Compare Cold fusion with other programming languages?

For every language has its pros and cons. Q5 is answer for this also, But I will point out one or 2 advantages of CF over other languages.
vs PHP : Ajax features, Integration with adobe products, community support, J2EE
vs Java : Easy to learn, Code developmet & maintence cost
vs .NET : All OS, Most of webserver Support

9.Difference between Cold fusion 5 and Cold fusion MX 6?

All versions of ColdFusion prior to 6.0 were written using Microsoft Visual C++. CF MX 6.0 move to the Java-based architecture. Major things introduced in CFMX (MX- Matrix, Code name is NEO- hero of Matrix). I pointed out some of them below,

Mac,Linux OS support
Flash Remoting
ability to code and debug Flash
API was released with an OOP
Added Verity Searches

10.Difference between Cold fusion MX 6 and Cold fusion MX 7?

Windows authentication introduced thorough "cfntauthenticate" tag
cfcompile utility introduced which used for Sourceless deployment
Administrator API: Change ColdFusion settings programmatically, without logging into the CF Administrator.
Gateways: SMS, IM (based on Extensible Messaging and Presence Protocol) gateways introduced
Flash forms , Skinnable XML forms introduced
New report builder introduced

11.What is “Application.cfm”?

When ColdFusion receives a request for an application page, it searches the page's directory for a file named Application.cfm. If one exists, the Application.cfm code is logically included at the beginning of that application page.
If your application runs on a UNIX platform, which is case-sensitive, you must spell Application.cfm with an initial capital letter.

12.Can we have multiple “Application.cfm” file in an Application?

Yes. If the application page directory does not have an Application.cfm page, ColdFusion searches up the directory tree until it finds an Application.cfm page. If several directories in the directory tree have an Application.cfm page, ColdFusion uses the first page it finds. If the Application.cfm page is present in the directory tree (and has the required permissions set), you cannot prevent ColdFusion from including it.
ColdFusion processes only one Application.cfm page for each request. If a ColdFusion page has a cfinclude tag pointing to an additional ColdFusion page, ColdFusion does not search for an Application.cfm page when it includes the additional page.

13.What is cfapplication tag?

It defines the scope of a ColdFusion application; enables and disables storage of Client variables; specifies the Client variable storage mechanism; enables Session variables; and sets Application variable time-outs.

14.How can you set the Client Management?

We can enable & disable client management as well as we can configure How & Where client variables need to be store

15.What are Session Timeout and Application Timeout? Where we have to do this process?

ApplicationTimeout : The time span an application will exist before it times out (if the application is not accessed in any way). This defaults to the value set in the ColdFusion administrator.
SessionTimeout :The time span a session will exist before it times out (if the application is not access in any way by that session's user). This defaults to the value set in the ColdFusion administrator.

16.How can you clear the cache?

To Flush cached queries <cfobjectcache action="clear">
To Flush cached pages <cfcache action="flush">

17.What are the differences between the different versions of the coldfusion?

Before CF6 MX coldfusion was implemented in Microsoft Visual C++.

18.Explain coldfusion architecture?

ColdFusion is a rapid application development environment that lets you build dynamic websites and Internet applications quickly and easily. ColdFusion consists of the following core elements:

• CFScript Engine
• CFML
• ColdFusion Administrator
• Verity Search Engine
• Extensions


• CFScript Engine
Coldfusion includes a built-in scripting language, CFScript, that let us write code in a
JavaScript fashion.


• ColdFusion Markup Language
ColdFusion Markup Language (CFML) is a tag-based language, similar to HTML, that uses special tags and
Functions.

• Coldfusion Administrator
ColdFusion Administrator configures and manages the ColdFusion application server. It is a secure web-based application like control panel that you can access using any web browser, from any computer with an Internet connection.


• Verity search Engine -
The Verity Search Server (also called the Verity search engine) provides full text search capability for documents and data on a ColdFusion site.


• Extension
  We can extend CFML further by creating custom tags or user-defined functions (UDFs), or by integrating COM,C++, and Java objects by using CFX tag.

19.Can we have multiple “Application.cfm” file in an Application?

Yes. If several directories in the directory tree have an Application.cfm page, ColdFusion uses the first page it finds.
If the Application.cfm page is present in the directory tree (and has the required permissions set), you cannot prevent ColdFusion from including it.

ColdFusion processes only one Application.cfm page for each request.
If a ColdFusion page has a cfinclude tag pointing to an additional ColdFusion page, ColdFusion does not search for an Application.cfm page when it includes the additional page.

20.What are different events in Aplication.cfc?

We can implement following events through Application.cfc –

• onApplicationStart:
  The very first time your application is used, the onApplicationStart event is broadcast. This gives you an opportunity to define some application-specific configuration.
  
  The important part to remember is that, as a rule of thumb, it only happens once, until your application times out the process is restarted, or the computer is restarted.


• onSessionStart:
  Any time that a user makes a request to your application and either they haven't used it before, or it's been long enough that their session has expired -- as identified by their cookies, usually -- the onSessionStartevent is broadcast.
  This allows you to set session defaults, like a flag indicating that the user is not currently logged in; or to redirect to the login page.


• onRequestStart:
  onRequestStart is broadcast before every request, giving you an opportunity to set variables that should be accessible on every page in the site, or to validate that the user is allowed access to the requested page, for instance.


• onRequest:
  onRequestStart is broadcast before onRequest, but they operate a little differently.


• onRequestEnd:
  Similarly to onRequestStart, onRequestEnd is broadcast after your template returns control to CF, giving you the opportunity to add code to every request after the requested template has executed.


• onSessionEnd:
  You can use this to do things like empty a shopping cart that was never paid for thus returning that reserved stock back to availability for other customers to buy.


• onApplicationEnd:
  This event is broadcast when your application times out or if ColdFusion is shutting down.


• onError:
  Lastly, there is an onError event broadcast in the event of an un-caught exception, including any you might manually throw.