[Dbix-class] DBIx::Class::Ordered changes.

[Will Crawford]

On 20 September 2012 11:19, Peter Rabbitson <rabbit+dbic at rabbit.us> wrote:

> I experimented with some stuff that is still on my disk, trying to set the
> nextpos to (SELECT pos .... ) + 1. It worked for most engines except for Pg
> for which this is not an atomic operation. Then I laughed at Pg and forgot
> about the whole thing. I need to get back to it at some point.

Ipricing=# create table test1 ( id serial primary key, value text );
NOTICE:  CREATE TABLE will create implicit sequence "test1_id_seq" for
serial column "test1.id"
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index
"test1_pkey" for table "test1"
CREATE TABLE
pricing=# create table test2 ( id serial primary key, test1_id integer
not null references test1, position integer not null, unique
(test1_id, position) );
NOTICE:  CREATE TABLE will create implicit sequence "test2_id_seq" for
serial column "test2.id"
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index
"test2_pkey" for table "test2"
NOTICE:  CREATE TABLE / UNIQUE will create implicit index
"test2_test1_id_position_key" for table "test2"
CREATE TABLE
pricing=# insert into test1 (value) values ('first');
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 0);
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 1);
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 2);
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 3);
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 5);
INSERT 0 1
pricing=# insert into test2 (test1_id, position) values (1, 4);
INSERT 0 1
pricing=# delete from test2 where test1_id = 1 and position = 2 ;
DELETE 1
pricing=# update test2 set position = position - 1 where test1_id = 1
and position between 3 and 5 ;
UPDATE 3