Re: [web2py] Re: talks
On Mon, Jul 4, 2011 at 7:13 AM, Massimo Di Pierro < massimo.dipie...@gmail.com> wrote: > It is somewhere in San Francisco. I only have 20minutes and I am told > to expect a tough crowd (mostly Django people). I will be driving to > SF from Lake Tahoe just for that. What should I cover? I should be able to get there, too, and can offer my impression from having just moved from Django to Web2Py! However, I can't figure out what group this is, either. Nick
Re: [web2py] Re: Best practice for inserting possible duplicates?
On Sat, Jul 2, 2011 at 7:39 PM, Anthony wrote: > Be careful about using an 'except' without specifying specific exception > types -- that code will attempt an insert regardless of the reason for the > failure in the 'try' clause. > I was wondering if someone would mention that... was just shortcutting! Nick
[web2py] Best practice for inserting possible duplicates?
Getting more comfortable with Web2Py and there sure is a lot to like about it. I'm wondering what is considered best practice for inserting records that might already exist, when I also want to get the id of the record if it does exist. I haven't come across a shortcut for this. For now, I'm using a try statement, as below, for a table that stores web page data: try: urlID = db.web_page(url=url).id except: urlID = db.web_page.insert(url=url) I notice that early last year there was a discussion of how to create the equivalent of Django's get_or_create(), which does this. I don't see that that even made its way into Web2Py. NIck
Re: [web2py] SQL UNIQUE IN WEB2PY : CONSTRAINT unique_test UNIQUE (num_part1, num_part2, num_part3, title)
On Fri, Jul 1, 2011 at 1:20 AM, Bruno Rocha wrote:
> Db.define_table('foo',Field('a'),Field('b'), Field('ab',unique=True,
> compute=lambda r: r.a + r.b))
>
This failed for me with sqlite and I see from other discussions that the
same is true with Django - sqlite throws an error that it cannot create a
unique field.
However, it seems to work fine with MySQL; it did create a unique index on
the column. I wasn't really planning to use sqlite, anyway, just thought
I'd keep things simpler at first. I just switched to MySQL now and it's
working fine.
Thanks for the help.
Nick
Re: [web2py] SQL UNIQUE IN WEB2PY : CONSTRAINT unique_test UNIQUE (num_part1, num_part2, num_part3, title)
On Thu, Jun 30, 2011 at 7:00 PM, Anthony wrote: > > > I don't think web2py automatically creates any indexes -- see > http://web2py.com/book/default/chapter/06#Indexes. > > It has to! Can't have primary keys without them. But I see what you mean, looking at the docs. I guess I will just use that approach to create a multi-column unique index but at this point I was really hoping to avoid raw SQL. Nick
Re: [web2py] SQL UNIQUE IN WEB2PY : CONSTRAINT unique_test UNIQUE (num_part1, num_part2, num_part3, title)
On Thu, Jun 30, 2011 at 6:43 PM, Nick Arnett wrote:
>
>
> On Thu, Jun 30, 2011 at 4:15 PM, Anthony wrote:
>
>> IS_NOT_IN_DB does take a DAL Set object as the first argument, so you can
>> limit the records checked to a particular set within the table (see
>> http://web2py.com/book/default/chapter/07#Database-Validators). However,
>> I'm not quite sure what you're trying to do here.
>>
>> I think what he wants is the equivalent of Django's "unique together",
> which I'm also trying to figure out. IS_NOT_IN_DB seems to accomplish it,
> but is that going to create a unique index on the combined fields?
> Otherwise, it will be expensive to do inserts.
>
Actually, I don't see how NOT_IN_DB can accomplish this, since it is
associated with a single field. Do I have to create an extra concatenated
field and make it unique? Seems silly, given that's what a database unique
index is.
In other words, for table foo, if I want fields A, B and C to be unique
together, do I have to do this?
db.define_table('foo', Field('A'), Field('B'), Field('C'),
Field('ABC_unique', unique=True))
And remember to concat A, B, and C into that last field every time I do an
insert?
I'm missing something here, since this is so simple elsewhere.
Nick
Re: [web2py] SQL UNIQUE IN WEB2PY : CONSTRAINT unique_test UNIQUE (num_part1, num_part2, num_part3, title)
On Thu, Jun 30, 2011 at 4:15 PM, Anthony wrote: > IS_NOT_IN_DB does take a DAL Set object as the first argument, so you can > limit the records checked to a particular set within the table (see > http://web2py.com/book/default/chapter/07#Database-Validators). However, > I'm not quite sure what you're trying to do here. > > I think what he wants is the equivalent of Django's "unique together", which I'm also trying to figure out. IS_NOT_IN_DB seems to accomplish it, but is that going to create a unique index on the combined fields? Otherwise, it will be expensive to do inserts. Nick
[web2py] Use the ORM for a robot?
I'm just getting to know Web2Py after working with Django a fair bit. I have robots that gather data that I would like to insert using the Web2Py ORM, but I can't quite figure out the right way to do that. If I put the bot scripts in the modules directory, I don't seem to have access to the ORM. When I run a module in the controllers directory, I can import from the modules directory with a simple import even though the documentation seems to say that I should use local_import... which doesn't work. And running a module in the controllers directory doesn't seem to give it access to the ORM, either. So... I'm lost and not finding the answer in the docs. In Django, I would just put the appropriate imports in the robot scripts, but I get that that's not the Web2Py way! Can anybody point me to an example of this sort of thing - inserting data that isn't coming from a request - or give me an idea of the right way to organize it into the Web2Py structure? Thanks in advance. Nick
