Rails - Nov 2009 - Which finder syntax would be preferred as far as being the most database agnostic?

Which finder syntax is preferred?  Or are they the same?

I''m developing on sqlite and I''ve posted the result of each
query...they kind of look the same but not really.  Would this scale
to say, Mysql or Postgres?  Thanks for any advice.

named_scope :disabled, :order => ''name'', :conditions =>
{ :disabled_at
=> !nil }
SELECT * FROM "groups" WHERE
("groups"."disabled_at" = ''t'') ORDER BY
name

or

named_scope :disabled, :order => ''name'', :conditions =>
[''disabled_at
<> ?'', nil]
SELECT * FROM "groups" WHERE (disabled_at <> NULL) ORDER BY name

I for one prefer the first syntax, since it eliminates SQL from the
ruby code, but that''s just my preference.

Cheers,
Tim

On Nov 4, 10:39 pm, Lee Smith
<autige...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> Which finder syntax is preferred?  Or are they the same?
>
> I''m developing on sqlite and I''ve posted the result of
each
> query...they kind of look the same but not really.  Would this scale
> to say, Mysql or Postgres?  Thanks for any advice.
>
> named_scope :disabled, :order => ''name'', :conditions
=> { :disabled_at
> => !nil }
> SELECT * FROM "groups" WHERE
("groups"."disabled_at" = ''t'') ORDER BY
> name
>
> or
>
> named_scope :disabled, :order => ''name'', :conditions
=> [''disabled_at
> <> ?'', nil]
> SELECT * FROM "groups" WHERE (disabled_at <> NULL) ORDER BY
name

Lee Smith wrote:
> Which finder syntax is preferred?  Or are they the same?
> 
> I''m developing on sqlite and I''ve posted the result of
each
> query...they kind of look the same but not really.  Would this scale
> to say, Mysql or Postgres?  Thanks for any advice.
> 
> named_scope :disabled, :order => ''name'', :conditions
=> { :disabled_at
> => !nil }
> SELECT * FROM "groups" WHERE
("groups"."disabled_at" = ''t'') ORDER BY
> name
> 
> or
> 
> named_scope :disabled, :order => ''name'', :conditions
=> [''disabled_at
> <> ?'', nil]
> SELECT * FROM "groups" WHERE (disabled_at <> NULL) ORDER BY
name
Use the first syntax -- the second one is incorrect.  I don''t know if 
this is true in SQLite, but in the other DBs, NULL = NULL returns NULL, 
so your <> NULL construct will return TRUE in all cases, and so it is 
pointless.  In the first case, Rails automatically generates the proper 
syntax.

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
-- 
Posted via http://www.ruby-forum.com/.

Marnen Laibow-Koser wrote:
> Lee Smith wrote:
>> Which finder syntax is preferred?  Or are they the same?
>> 
>> I''m developing on sqlite and I''ve posted the result
of each
>> query...they kind of look the same but not really.  Would this scale
>> to say, Mysql or Postgres?  Thanks for any advice.
>> 
>> named_scope :disabled, :order => ''name'',
:conditions => { :disabled_at
>> => !nil }
>> SELECT * FROM "groups" WHERE
("groups"."disabled_at" = ''t'') ORDER BY
>> name
>> 
>> or
>> 
>> named_scope :disabled, :order => ''name'',
:conditions => [''disabled_at
>> <> ?'', nil]
>> SELECT * FROM "groups" WHERE (disabled_at <> NULL)
ORDER BY name
> 
> Use the first syntax -- the second one is incorrect.  I don''t know
if
> this is true in SQLite, but in the other DBs, NULL = NULL returns NULL, 
> so your <> NULL construct will return TRUE in all cases, and so it is
> pointless.  In the first case, Rails automatically generates the proper 
> syntax.
On second thought, *both* are incorrect.  Use :conditions => 
''disabled_at is not null''.

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
> 
> Best,
> --
> Marnen Laibow-Koser
> http://www.marnen.org
> marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
-- 
Posted via http://www.ruby-forum.com/.

On Nov 5, 1:19 pm, Marnen Laibow-Koser <rails-mailing-l...@andreas-
s.net> wrote:
>
>
> > named_scope :disabled, :order => ''name'',
:conditions => [''disabled_at
> > <> ?'', nil]
> > SELECT * FROM "groups" WHERE (disabled_at <> NULL)
ORDER BY name
>
> Use the first syntax -- the second one is incorrect.  I don''t know
if
> this is true in SQLite, but in the other DBs, NULL = NULL returns NULL,
> so your <> NULL construct will return TRUE in all cases, and so it is
> pointless.  In the first case, Rails automatically generates the proper
> syntax.
Actually NULL <> NULL is also NULL. Hooray for 3 way logic.
(doesn''t
mean the OP''s would work though). In general I tend to use the hash
form of conditions when possible, but that''s not always the case.

Fred
>
> Best,
> --
> Marnen Laibow-Koserhttp://www.marnen.org
> mar...-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
> --
> Posted viahttp://www.ruby-forum.com/.