well, I am posting in trunk a modifiled sql.py that

allows Field('name','autoincrement') and generates the following code
for postgresql (only postgresql). Give it a try.

Massimo

On Jun 9, 10:38 am, Thadeus Burgess <thade...@thadeusb.com> wrote:
> Postgres
>
> CREATE TABLE foo (
> id integer PRIMARY KEY SERIAL,
> bar varchar,
> did integer DEFAULT SERIAL);
>
> Or...
>
> CREATE SEQUENCE seq_foo_did START 20000;
>
> CREATE TABLE foo (
> id integer PRIMARY KEY SERIAL,
> bar varchar,
> did integer DEFAULT nextval('seq_foo_did'));
>
> SQLite however does not support multiple auto-increment fields
> unfortunately, so on sqlite it must be done the way of creating
> another table with a blank field and use its id as a sequence
> (basically like how postgres does behind the scenes).
>
> MySQL also supports multiple autonumber fields.
>
> Having two autonumber fields is an absolute requirement of the system
> and there is no way around this. Unfortunately I don't have time to
> work on implementing this in web2py, and I could probably re-write my
> app in something else faster than it would take me to implement this
> in the DAL since I am not familiar enough with the DALs internal
> quirks.
>
> I can't do anything for at least 3 weeks programming wise, so I won't
> even be getting around to fixing this issue until then.
>
> --
> Thadeus
>
> On Wed, Jun 9, 2010 at 9:26 AM, mdipierro <mdipie...@cs.depaul.edu> wrote:
> > I am not sure about the postgresql solution. Tell me how you do it in
> > SQL and i tell you how to do in web2pyese.
>
> > On Jun 9, 9:01 am, Thadeus Burgess <thade...@thadeusb.com> wrote:
> >> Great. What about sqlite?
>
> >> --
> >> Thadeus
>
> >> On Wed, Jun 9, 2010 at 8:41 AM, mdipierro <mdipie...@cs.depaul.edu> wrote:
> >> > In postgresql you get it native:
>
> >> > Field('yourtfield',SQLCustomType('integer','SERIAL PRIMARY
> >> > KEY',encoder=(lambda x: int(x)),decoder=(lambda x:x)))
>
> >> > On Jun 9, 5:28 am, Thadeus Burgess <thade...@thadeusb.com> wrote:
> >> >> That is the thing, its *almost* the same, but its not a true postgres
> >> >> sequence. Postgres already has many years of development making sure
> >> >> their auto number works, why can't I just use that instead of trying
> >> >> to hack around the limitations of a system?
>
> >> >> I don't have a choice. I *must* have native support for autonumber, or
> >> >> I have to use another system that already allows me to.
>
> >> >> --
> >> >> Thadeus
>
> >> >> On Tue, Jun 8, 2010 at 10:22 PM, mdipierro <mdipie...@cs.depaul.edu> 
> >> >> wrote:
> >> >> > If it were possible to do a SQL insert without the dummy filed this
> >> >> > almost the same as creating a sequence. web2py can create a table
> >> >> > without any field but the "id", but I do not do not how to do an
> >> >> > insert without any field value.
>
> >> >> > On Jun 8, 8:12 pm, Thadeus Burgess <thade...@thadeusb.com> wrote:
> >> >> >> This *might* work. You are right, it is still horrible... It might be
> >> >> >> *effectively* accomplishing the same thing that sequences do on
> >> >> >> PostgreSQL, however I still wouldn't use it in production as it feels
> >> >> >> "hacky". I already have to re-design this table, so I might as well 
> >> >> >> do
> >> >> >> it 100% right.
>
> >> >> >> I never expected the scale of inserts that happened yesterday and
> >> >> >> today, nor had any proper benchmarking been done previously if it
> >> >> >> could handle this kind of sudden rush of traffic.
>
> >> >> >> --
> >> >> >> Thadeus
>
> >> >> >> On Tue, Jun 8, 2010 at 4:36 PM, mdipierro <mdipie...@cs.depaul.edu> 
> >> >> >> wrote:
> >> >> >> > I know this horrible but it does solve some of the problems...
>
> >> >> >> > db.define_table('whopper_seq',Field('dummy'))
>
> >> >> >> > db.define_table('yourtable',...
> >> >> >> > Field("whopper_id", "integer",compute=lambda r:
> >> >> >> > db.whopper_seq.insert(dummy=None))
> >> >> >> > ...)
>
> >> >> >> > On Jun 7, 8:29 pm, Thadeus Burgess <thade...@thadeusb.com> wrote:
> >> >> >> >> I have a problem.
>
> >> >> >> >> I have this in the database....
>
> >> >> >> >> Field("whopper_id", "string", default=None, unique=True),
>
> >> >> >> >> The thing with whopper_id is it always stores numbers. Said 
> >> >> >> >> numbers
> >> >> >> >> are anywhere from 20000 to 60000.
>
> >> >> >> >> Also upon entering a new entry, I do the following
>
> >> >> >> >> last_whopper_id = db(db.table.id > 0).select(db.table.whopper_id,
> >> >> >> >> orderby=~db.table.whopper_id, limit=(0,1)).first().whopper_id
> >> >> >> >> db.insert(whopper_id = (int(last_whopper_id) + 1))
>
> >> >> >> >> So I do all this juju just to get the number to autoincrement.
>
> >> >> >> >> The problem is, this structure is bad... first I'm storing 
> >> >> >> >> integers in
> >> >> >> >> a string field, and then manually incrementing them!!!!
>
> >> >> >> >> I get errors like... IntegrityError: duplicate key value violates
> >> >> >> >> unique constraint "table_whopper_id_key"... when two requests 
> >> >> >> >> come in
> >> >> >> >> to create a record within miliseconds of each other.
>
> >> >> >> >> Here is where I need some help please.
>
> >> >> >> >> I need to convert this entire field, into an autoincrementing 
> >> >> >> >> integer
> >> >> >> >> performed by the database, however ALL current whopper_ids must 
> >> >> >> >> stay
> >> >> >> >> EXACTLY the same.
>
> >> >> >> >> I don't know how to accomplish this with web2py. I know what I 
> >> >> >> >> want...
>
> >> >> >> >> Field("whopper_id", "integer", unique=True, autoincrement=True)
>
> >> >> >> >> But how do I convert all existing whopper_ids over and keep them 
> >> >> >> >> the exact same?
>
> >> >> >> >> Is this even possible with web2py and the DAL?
>
> >> >> >> >> --
> >> >> >> >> Thadeus

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