2011/11/8 danto <web2py.n...@gmail.com> <<<<<<<< that was me, sorry
> > 2011/11/8 BrendanC <bren...@gmail.com> > >> Daniel, >> Not sure what you are asking, but this might help you: >> >> Virtual fields are otherwise known as 'computed columns' in database >> terms - if that is what you are familiar with. e.g. Sum, Count, Min, Max, >> etc as these values are derived from underlying table data in a database. >> >> A database view is something entirely different - think of it as a >> virtual table or a stored query than can expose either a subset of table >> columns or a query that joins multiple tables and shows just the columns >> you want. Views are very commonly used in legacy type applications (for >> security and performance reasons - e.g. hide the employee salary info by >> creating a view that excludes that data element). >> >> > I don't know when I start confusing Virtual Fields with Virtual Tables, an > so I was overestimating what I can do with Virtual Fields. > > When you said "is commonly used in legacy applications" you mean that now > they are not used very much? IIRC, Views are a lot faster than doing a Join > from the app. > > >> In the world of web development (Web2py, Django, Rails etc) database >> access is managed primarily by ORM's. For the most part these are not very >> 'View' friendly - you have to jump through a few hoops to use a view and >> there are some also potential maintenance issues. (FWIW views are very >> useful for simplifying complex queries and it's a pity that they are not >> well supported in most web environments). >> >> Hope this helps, >> BrendanC >> >> > > I'm agree with you. I also can't understand why Databases Views are not so > important in Web2py (et al). The only way I see to use Database's Views in > web2py is with db.extecutesql statement. I hope some other can answer us. > > Thank you Brendan! You helped me a lot. > > -- Daniel Aguayo @dantoac GNU/Linux User #387337
