ASP runs only in windows ( can also run on Linux but not supported by many host and not so compatible), while php runs on both Linux and windows server. So its clear that ASP is most expensive to run coz we need window server and then iis .. even though iis is free but window server cost much more.



Database:

ASP supports all databases but its best run with access and ms sql. If your application requires more users and more constant hit then ASP is better coz you can use mssql which is far better than mysql. But if you have fewer users then you can also use access with asp but the main problem with access is, it cant handle more concurrent hits and crashes most of the time. ASP doesn't runs well with mysql, you may get problems on paging . PHP runs best with mysql, and also support mssql. Best part of mysql with php is its more versatile and easy in compare to asp with mssql. MYsql is simple and easy to use while mssql is more complex. If your database size is less than 2GB then you must use mysql with PHP but if you have high size database then mssql is the option.

The main draw back of asp code on database is, when you create record set asp will load all the data to the record set . So no matter you are showing few records , yours recordset is holding lots of data and if you have 10000's of records your asp application may hang. So you must use Store Procedure with mssql or view with access. But in PHP you dont have that problem.

Programming comfortable:

If you know both asp and php language programming is easy on both side. PHP is more c/c++ style programming but that doesn't mean that you have to program is oops way. ASP is more VB style programming. As per the online resources is concern you will get php recourses more than asp. With php you can also easily work on server related programming like dns, meta data e.t.c but in asp its very hard to work on server side manipulation and you need special permission to do that from admin. Many Window server provider dont give you advance access that you need to work for asp program like folder permission, root parent path enable e.t.c while in php you can do it easy with ftp command.

Business point of view:

Mainly customers dont know what programming language , they need their program on. but many have cheap hosting with linux so they may ask you to make on php. Since there are many php programmer in comparison with asp one, you may have chance to get more work being asp programmer. But it just assumption. As per my experience making program on asp is more profitable than in asp as many programmer or business owner they get less asp programmer and for advance programming you can find your customer easily. while in php there are many php programmer so competition is high and even though demand is high, you chance of getting work is less... ( just a perception)

Extra cost:

Many add-ons for php are free ( if hosted on Linux). but with asp you need to pay for almost everything like mail component, ftp component, image upload component e.t.c

Conclusion:

By above idea we can say that PHP Programming is cheaper than ASP programming. but with database if you have complicated requirement i suggest ASP than php. As per the programming is concern, since resources of php are widely available than asp so its easy to program php than asp but as per the syntax and programming concern its of no difference.