Re: [xsl] XPath equivalent of a join

["Aaron Luke" <bluenike@xxxxxxxxx>]

BTW, if instead of 1501 classes x 1501 teacher, there are 1501 classes
x 1 teacher or 1 class x 1500 teachers, the running times are only 1
second and 3 seconds respectively.

On 7/14/07, Aaron Luke <bluenike@xxxxxxxxx> wrote:
> Hi-
>
> Thanks for your solution... the only problem is that this solution
> seems to run very slowly.
> If I replicate 1500 copies of the class with id="2" and 1500 with the
> teacher with id="9",
> then the query takes almost 30 seconds using Saxon8 on a 2Ghz Core 2
> Duo even though
> the query only matches 1 record.  Any ideas on speeding that up?
>
> I included a fixed version of the xml doc below, too.
>
> Aaron
>
>   <root>
>      <class id="1">
>            <teacher>5</teacher>
>          </class>
>      <class id="2">
>            <teacher>9</teacher>
>          </class>
>
>      <teacher id="5">
>            <gender>female</gender>
>          </teacher>
>      <teacher id="9">
>            <gender>male</gender>
>          </teacher>
>   </root>
>
>
>
> On 7/14/07, Mukul Gandhi <gandhi.mukul@xxxxxxxxx> wrote:
> > Your input XML is not as per the XML spec (there should be double
> > quotes around attribute values).
> >
> > If the above error is corrected in the XML, I found the following
> > solution to work:
> >
> > <?xml version="1.0"?>
> > <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
> > version="1.0">
> >
> >   <xsl:output method="xml" indent="yes" />
> >
> >   <xsl:template match="/root">
> >     <result>
> >       <xsl:copy-of select="class[teacher = ../teacher[gender =
> > 'female']/@id]" />
> >     </result>
> >   </xsl:template>
> >
> > </xsl:stylesheet>
> >
> > On 7/14/07, Aaron Luke <bluenike@xxxxxxxxx> wrote:
> > > Hi all-
> > >
> > > Given the following document:
> > >
> > > <root>
> > >  <class id="1">
> > >    <teacher>5</teacher>
> > >  </class>
> > >  <class id="2">
> > >    <teacher>9</teacher>
> > >  </class>
> > >
> > >  <teacher id=5>
> > >    <gender>female</gender>
> > >  </teacher>
> > >  <teacher id=9>
> > >    <gender>male</gender>
> > >  </teacher>
> > > </root>
> > >
> > > Is there an XPath statement that selects all of the classes taught by
> > > female teachers (in this case, just the first class)?
> > > The field class.teacher is an id reference to teacher.id.
> > >
> > > In sql, I would be looking for:
> > >
> > > select class.* from class c, teacher t where c.teacher=t.id and
> > > t.gender='female';
> > >
> > > Can't seem to figure this one out- any help would be appreciated.
> > >
> > > Aaron
> >
> >
> > --
> > Regards,
> > Mukul Gandhi