Re: [OJB-developers] OJB DISTINCT

[Jakob B. <jbr...@ho...>]

hi dirk,

there's a setDistinct(boolean) in QueryByCriteria. The third attribute is
only for convenience.

jakob

----- Original Message -----
From: "Dirk Olmes" <di...@xa...>
To: "Jakob Braeuchi" <jbr...@ho...>
Cc: "Objectbridge Developers List (E-mail)"
<obj...@li...>
Sent: Monday, December 10, 2001 12:56 PM
Subject: Re: [OJB-developers] OJB DISTINCT


> > the attached zip enables setting DISTINCT in sql-queries.
> > there are new constructors in QueryFactory with an additional boolean
> > parameter 'distinct'.
> >
> > the following snippet shows a sample (one person has many accounts and
> > many
> > telephones) and the generated sql.
> > the sql also shows, that multiple joins work:
> >
> > Query query;
> > Criteria crit;
> >
> > System.out.println("\nread all person with konti.saldo > 200 and tel
> > like
> > 031%");
> > crit = new Criteria();
> > crit.addGreaterThan("konti.saldo",new Integer(100));
> > crit.addLike("telefone.nummer","031%");
> > query = new QueryByCriteria(Person.class, crit,true);         // true ->
> > DISTINCT
>
> Not knowing much of the internals of OJB (I dug into the source once but
> this is long time gone) I find the third argument to the constructor
> awkward API.
>
> Wouldn't it be clearer API to be able to write:
>
> crit = new Criteria();
> crit.addGreaterThan("konti.saldo",new Integer(100));
> crit.addLike("telefone.nummer","031%");4
> crit.setUsesDistinct(true);
> query = new QueryByCriteria(Person.class, crit);
>
> Just my thoughts,
>
> -dirk
>
>