Ok, so this is kinda out of the blue… but I’ve been looking at
Google Base and thinking that it’s got some really good ideas in it.
Especially the way you can create your own “type” of item with its own
custom attributes, like date range, location, number, text, etc. Kind
of like defining a database with a GUI, but not exactly.
It seems really interesting to me, from a sort of content management
perspective. The hardest part for me is getting my head around how
you’d structure the database tables to do this. It’s a lot like making
an application that lets users build their own surveys, if that makes
sense. Is anyone working on something remotely like this?
in essence…
table Models
table Fields
class Model < AR, etc
has_many :fields
end
On Tuesday, April 11, 2006, at 12:17 AM, Raymond B. wrote:
sense. Is anyone working on something remotely like this?
Rails mailing list
[email protected]
http://lists.rubyonrails.org/mailman/listinfo/rails
Mikkel B.
www.strongside.dk - Football Portal(DK)
ting.minline.dk - Buy Old Stuff!(DK)
Mikkel B. wrote:
in essence…
table Models
table Fields
class Model < AR, etc
has_many :fields
end
On Tuesday, April 11, 2006, at 12:17 AM, Raymond B. wrote:
sense. Is anyone working on something remotely like this?
Rails mailing list
[email protected]
http://lists.rubyonrails.org/mailman/listinfo/rails
Mikkel B.
www.strongside.dk - Football Portal(DK)
ting.minline.dk - Buy Old Stuff!(DK)
There is one written in rails, but it isn’t so good and I can’t remember
the url.
On 11/04/2006, at 7:17 PM, Raymond B. wrote:
It seems really interesting to me, from a sort of content management
perspective. The hardest part for me is getting my head around how
you’d structure the database tables to do this. It’s a lot like making
an application that lets users build their own surveys, if that makes
sense. Is anyone working on something remotely like this?
I’m working on something that’s very vaguely similar. It’s not of the
scaled that Google Base is, but the fields can contain various types
of data.
The easiest way is to have two tables, on with field descriptions and
one with data. However, when a customer calls up asking you to do a
complex data query it gets tricky. I’ve come up with a postgresql
specific system that dynamically creates and modifies the data
storage tables for each user. It’s probably far more complicated than
it needs to be and a bit fragile in some places, but it works. As a
bonus it gives you a real ActiveRecord object, though you can’t use
the association methods.
There is one written in rails, but it isn’t so good and I can’t remember
the url.
Hi Joey,
Do you mean http://www.myowndb.com ?
Why the not so good? Let me know, I’m interested! ( You’re the first
negative comment I see about the app.)
It’s in full development and has had some additions since the
announcement (see Index of /blog )
Cheers
Raph
On 4/11/06, Phillip H. [email protected] wrote:
The easiest way is to have two tables, on with field descriptions and
one with data.
The problem I’m having trouble getting my head around - or finding
code samples for - is letting folks create their own data set. Let’s
call it a Survey. I want users to be able to create any number of
Surveys, each of which contain a number of “rows” just like in a
database. How would you store the fact that one survey “question”
takes a text area, and one takes a date, and one takes an integer,
etc.?
Can anybody suggest a not-so-fragile, best-practice way of tackling
something like this in a database?
class Set < ActiveRecord:Base
has_many :rows
end
class Row < ActiveRecord:Base
belongs_to :set
has an id, a type, a Text field called “value”
end
class IntegerRow < Row
def value
super.value.to_i
end
def value=(input)
super.value = input.to_s
end
end
class TextRow < Row
#no accessors needed
end
So, basically what we are using is the subclass idea built into Rails.
There
are only two tables in the db in this example, but “types” associated
with
each row. In my super-simple example, a TypeRow is just an accessor
wrapper
around a Text field in the db that does converstion.
You won’t have the smallest DB in the world and you couldn’t do built-in
db
calculations on numbers.
But, otherwise you could go crazy defining rows… “PersonRow” could
return
a first and last name, etc.
-hampton.
-hampton.