Marrying HTML and Databases using Active Server Pages JJ Cadiz

Outline Who is this JJ guy? What can you do with ASP? How does ASP work? Hardware & Software requirements Data access using ASP Example ASP systems

Things I won’t cover Security Visual Basic Script Java Script Client-side scripting Scalability »Concurrency »Big web sites don’t use MS Access (I hope)

About my background... Masters of HCI student, class of 99 Work full time on a CMU research team Have used ASP heavily for past two years »data collection »experimental tools development Joining Microsoft Research in August

What can you do with ASP?

Example sites Microsoft tech support site support.microsoft.com On-line stores On-line auction houses

ASP jobs If you can marry databases and HTML, there are companies who want you Search job web sites using keywords “active server pages” »careers.wsj.com »

The Mental Model of ASP

Normal HTML 1. Client requests an html page 2. Server sends client html page

Dynamic HTML with ASP 1. Client requests an.asp file 2. Server processes.asp file, which generates HTML 3. Server sends generated HTML to client

ASP, SQL, Databases, and HTML Web Server Client Browser - Internet Explorer - Netscape Navigator Database(s) HTML ASP VBScript & SQL

Hardware & Software for ASP

Server Requirements You can’t do ASP on Andrew ASP requires an MS Windows environment »NT Server with Internet Information Server »NT Workstation with “Peer Web Services” (10-user connection limit) »Win95/98 with Personal Web Server

Developer Tools Your favorite HTML editor Your favorite script/code editor A database (Access, Oracle, SQLServer) My favorite: MS InterDev

Data Access using ASP

Queries in ASP: The Recordset The mental model of a recordset How to create and use a recordset in ASP Example system: Employee compensation database

Creating Recordsets in ASP ‘ Establish connection to database Set empCompConn = Server.CreateObject("ADODB.Connection") empCompConn.Open ”empComp” ‘empComp must be a DSN ‘ Create the SQL Command and link it to our database Set empCompCmd = Server.CreateObject("ADODB.Command") Set empCompCmd.ActiveConnection = empCompConn empCompCmd.CommandText = "SELECT * FROM Compensation" ‘ Create the recordset and link it to the command Set empCompRS = Server.CreateObject("ADODB.RecordSet") Set empCompRS.Source = empCompCmd empCompRS.LockType = adLockPessimistic empCompRS.Open … empCompRS.Close

Reusing Recordset Objects empCompRS.Close empCompCmd.CommandText = "SELECT * FROM Compensation ORDER BY Salary DESC" empCompRS.Open

Navigating Recordsets in ASP empCompRS.Move #rows empCompRS.MoveFirst empCompRS.MoveLast empCompRS.MoveNext empCompRS.MovePrevious empCompRS.EOF ‘ JJ’s favorite loop empCompRS.Open While(not empCompRS.EOF) DoMagic empCompRS.MoveNext Wend empCompRS.Close

Accessing Fields Moving data from the database to ASP Dim salary salary = empCompRS.Fields("salary").Value Moving data from ASP to the database... empCompRS.Fields("options").Value =

Creating and Editing Records Editing existing records empCompRS.Edit... empCompRS.Update Creating records ‘ Doesn’t matter where the record pointer is when you do this ‘ Make sure to ensure unique keys when adding records! empCompRS.AddNew... empCompRS.Update

Creating and Editing Records Example: For all the employees making less than $53,000/year: »Increase everyone’s salary by $5000/year »Decrease everyone’s stock options by 250/year Add an employee who makes $54,000 and receives 100 options each year

Putting it all together: Authoring ASP pages

ASP File Structure ASP commands go inside tags Script code goes inside tags Anything outside of these tags is HTML Comments inside ASP or Script code are prefaced by a single quote <% ‘ Good programmers write lots of comments! %>

A simple ASP file <% ' Simple ASP code that gives the appropriate greeting based on the time of day ' Get the time of day Dim currentTime currentTime = now ' Output the correct greeting based on whether it's morning, ' afternoon, or evening if(currentTime >= #5:00am#) AND (currentTime < #12:00pm#) then %> Good morning! = #12:00pm#) AND (currentTime Good afternoon! Good evening! The current time is

Now let’s design a system... An on-line store The story... What should our product be? How much should it cost? Orders taken via credit card and shipped via UPS

The design Design the database Design the HTML pages Tell me what the ASP code needs to do