Deciphering Website Design - WebProgramming, Databases & AJAX

Unlike Javascript, web programming languages are fullinformation in. One of the tables is to store email
fledged programming languages. They are also knownaddresses for your visitor, maybe another one for
as server-side programming languages because ayour blog, and maybe another one for your members
server translates the code and then returns thearea account information.
necessary information back to the browser in HTMLHow would you communicate with the database
format. So if you ever see webpages ending in .phpthough? Good news, there is a standard language in
or .cfm or .aspx in your address bar then that pageplace that is used to communicate with databases.
was created using a web programming language.It's known as SQL Query Language, not to be
How does a web programming language workconfused with SQL Server. SQL, Structured Query
though?Language, is not a programming language, it's a
Well we first talked about HTML, which is just staticcomputer language that's used by almost all major
data - meaning that the information on the webpagedatabases which allows you to write queries that can
doesn't change unless someone manually changes it.be run to access and manage the data stored on
With a web programming though every time a webyour database. You can write a query that brings
programming language loads it can bring back newback the newest record for the newest member.
information directly from say a database. Let's sayThe database will execute the query and bring back
you're a web programmer and you want to displaythat information for you.
dynamic information on the webpage by bringingWhat if you have specific information that you want
something from the database, maybe the mostto search for, like a book on Your web programming
recent member that joined your website. Let'slanguage will take the information which you entered
assume you have a small database, we'll talk moreinto the search box on the webpage and then once
about database in the next section, and it stores theyou click go it will take what you entered and
name and email addresses of the members thatcombine it with the SQL query and send it off to the
have signed up to your newsletter.database to let the database try and find that book.
A web programmer will start with a webpage similarOnce the database finds the book it brings that back
to a normal html/xhtml webpage. They'll then addand the web programming language will display it
code on the page using the programming languageaccordingly.
and change the name of file to something likeYou can also use SQL for searching for information,
NewMembersName.cfm instead ofadding new information, updating information, deleting
NewMembersName.html. They'll then upload the file toinformation and other advanced queries. I say
their website host, just like you would upload aadvanced because if you want to store tons and
normal html file. But in this case it will work a bittons of data and manage it correctly then you'll need
differently. Normally when an HTML file is requestedto work with a RDBMS, a Relational Database
the server just sends all the information to yourManagement System.
browser and your browser displays it for you, that'sWhy RDBMS? Well let's say you went to and you
why HTML is static. In the case of a webbought a book. The Amazon database creates a
programming language, the process works a littlerecord and then remembers that you bought this
differently.book. But what if you decided to buy 2 or 5 books,
If you request example.com/newmembersname.cfmwould it make 5 additional accounts with your names
then the server will first parse through the code onand address along for each of the 5 different books
that page, and then once it's found the newestthat you bought. NO.
member from the database it will display thatRelational Databases are used in such cases to
information where the programmer originally wanteddecrease redundancy ie: get rid of repetitive
it placed on the webpage.information. An RDBMS database is designed so that
Then once it's finished the webpage is sent back tothe tables are tied, related, to each other and they
your browser. And since the information that it sendsknow how to manage information correctly.
to your browser is only the pure html you're browserIn this case they'll have a table for your account and
can easily display it correctly. This is why it's calledanother table which keeps a track of all Amazon
Server Side Programming because it doesn't matterproducts. Now in realtiy I'm sure Amazon has more
whether your browser supports Coldfusion MX, PHPthen just two tables infact an RDBMS system can
or other languages because it's the server's job tooften take up dozens and dozens of tables to help
decipher that programming language and turn it intoincrease efficiency, and help reduce redundant
HTML that you're browser can easily understand.information.
If you tried to upload a newmembersname.php file toThere you have it. Now you know how the website
a server that didn't support that programmingdevelopment technologies work and how they all fit
language then the server wouldn't know what to doin together. For more about Website Development
with that file and it would just allow you to downloadvisit a resource that is number one of my list of
the file normally, along with the code that thebookmarks: Here are some links that you might also
programmer used. But since the server, atleast in thislike:
scenario, does support Coldfusion MX it wouldn'tCSSZengarden.com,
display any of that code to you, only the parsedSitePoint.com,
HTML.Wikipedia CSS - en.wikipedia.org/wiki
When I first saw a dynamic page I used to wonderCascading_Style_Sheets
what makes this page so special, the code looks justSo what's next. If you're interested in furthering your
like HTML. Well that's because it is HTML it's just thatskills then I would suggest learning more about AJAX.
the server had already translated the webAjax is not a language. It's actually a methodology
programming language that was part of the .cfmwhich combines several technologies that are already
page and turned it into HTML that you're browseravailable and combines them in such a way that it
can easily understand.makes AJAX websites appear dynamic, almost like
Viola, and that is how a Web Programming / Serverthe software installed on your computer. In normal
Side languages work. You'll find commonly used webweb page you would type in the name of a book.
programming such as PHP, ColdFusion MX, andOnce you press enter, the webpage forwards that
ASP.NET. Php is free and open source and you caninformation which is sent to server-side programming
usually see it in action for files ending with .phplanguage which then adds it to an SQL query to
extensions. Coldfusion was originally developed bysearch the database for that book. Once you're on
Allaire which was then acquired by Macromedia, whichthe next page that information is displayed on that
is now part of Adobe Systems. Yes the samepage.
company that created Adobe Photoshop and theBUT with AJAX once you press enter the AJAX
PDF file format. ASP.Net is part of the Microsoft .NETtakes over. The DHTML detects your click, calls on
framework. I'm a big fan of Coldfusion MX, so you'llthe javascript, which uses DOM - Document object
have to believe me when I say ColdFusion MX is themodel to access the information you entered. The
best in this galaxy, unless you think I might be a bitJavascript then sends that information to a web
biased. Oh well.programming page. The webprogramming language,
Allright you've gotten this far, might as well read upwhich ever one you decide to use, checks to see if
on how databases fit into the whole schema ofthat books is available in the database. If the book is
things. Actually the concept of database is fairly easythere then that information is sent back to the
to understand. It's used to store information. I meanbrowser. The Javascript, using XMLHttp, detects that
just think about it, without a database how wouldthe information has arrived and then uses DOM to
Hotmail verify you're password, how would MySpaceshow the information back onto the webpage
remember the comments that you left on yourwithout the webpage ever refreshing. The effect are
friend's myspace page which you wish you hadn'tpretty amazing.
when you were drunk.. Moving on. That's because itI'm sure as the web evolves we'll see more and
was stored on a database. There are severalmore amazing technologies. If you're interested in
different databases. You've proabably heard ofkeeping up-to-date with these technologies then I
Microsoft SQL Server, Oracle, MySQL which iswould recommend subscribing to some of top
opensource and free database, and also Microsoftnewsletters in the industry - CNet, ZDNet, SitePoint,
Access.and Lockergnome.
To speed things along let's just assume that you'veEnjoy!
created a database and also a few tables to store