Thx for the speedy reply. Here's another question: 3) Because I'm doing a thick client, it creates db queries (SQL CRUD) which need to be communicated back to the controller which must query the db. The two ways to do this are:
a) use a SQL statement within a executesql command, or b) create a DAL row selection criteria string and a column selection criteria string, send them back to the controller which feeds them through a python eval statement within a DAL function. It is always pointed out that b) is dangerous because it's possible for unintended string matter to get fed into the eval - which can reek havoc. However only *my* strings from the client which I have carefully massaged will ever be sent (e.g. I collect the column names from the db beforehand and provide them to the db().select(<fieldnames- here>) statement). Further, if I craft a SQL string then it too can suffer from bad input. I just have to be extra careful when creating the query strings. However if I use a) then I lose all of the functionality provided by the DAL. I've never been a fan of SQL and I'd like to avoid it in favour of what the DAL can offer. So I've implemented b) and it is working. My questions are: i) am I missing the obvious? Is there a much simpler/better way to do this? ii) does the DAL add much overhead? On Jul 9, 9:21 pm, mdipierro <mdipie...@cs.depaul.edu> wrote: > On Jul 9, 11:04 pm, rb <rbspg...@gmail.com> wrote: > > > Hi all, > > > I'm using Web2py to serve a wxPython thick client via XMLRPC. I'm > > currently using SQLite (I like the zero db config ;-) and I have a few > > questions: > > > 1) I have missed how to specify table constraints across several > > fields (in SQLite). For example, in a table the primary key consists > > of two fields - how do I specify that these two fields must comprise a > > UNIQUE value? In other dbs I could use executesql to just give the SQL > > commands, but SQLite (unless I'm mistaken) only allows table > > constraints within the CREATE TABLE SQL command. So can this be done > > in Web2py? > > You cannot create such constraint database side from > web2py. Your options are: > 1) enforce the constraint at the validators level > 2) create the table outside web2py and set migrate=False > > > 2) I'm confused as to which models get run when a controller is > > accessed. If I have db.py and uom.py models and I access the uom > > controller, what happens? From stepping thru the debugger I saw db.py > > get run first, then uom.py and then uom.py again (weird). I've > > simplified things down to just one (db.py) file for now, but I'm > > wondering if the infrastructure's intent is to run all model files > > upon each and every controller access. Oh, my access of the controller > > is via XMLRPC function (if that changes anything). > > All of them. Alphabetically. There has been some discussion on whether > there should be exceptions to this rule. It would be easy to inplmenet > but there was no consensus on whether an improvement was necessary. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py Web Framework" group. To post to this group, send email to web2py@googlegroups.com To unsubscribe from this group, send email to web2py+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
