 | | | Performance Issue | Performance Issue 2007-04-05 - By Henry Zongaro
Hello.
"alapati.sasi" <alapati.sasi@(protected)> wrote on 2007-04-04 02:47:28 PM:
> i need to transform a big source xml into target xml . My source xml
comes
> with the namespace prefix and my xsl doesnt contain any prefixes for
xpath.
>
> its very difficult to change all the xpath's at run time for me .
>
> i have two options
> 1) First change the source xml to another xml file using
[HZ: Removed stylesheet to create copy using just local names, no
namespaces]
> this template .This will remove all the prefix bindings .
> Now apply my original style sheet .I Will get the target xml.
> Is this cause me performace hit ?
> Is it better to do like this or Is it better to have local-name() in the
> stylesheet itself so that there is no additinal transformation required
.
> But if i use local-name() for all the xpath's i heard that processing
time
> will take more time ?
You're right that using a path expression like "*[local-name()='foo']"
will not perform as well as using the expression "foo" or "p:foo". My
instinctive reaction is that your other alternative of using a
preprocessing stylesheet that strips out namespaces will probably perform
worse. If the input to a stylesheet is very large, the time spent
constructing the input data model and serializing the result (assuming
that that is about as large) often dominates the performance; in this
case, you would be doing all of that twice. However, it really depends on
your particular XML and XSL. Your best bet would probably be to prototype
both solutions, and see how they perform for your particular.
If you're using the SAX API to deliver your XML to your stylesheet,
another option might be to apply some filtering of the SAX events that
removes namespace declarations, and changes element and attribute names to
equivalent, non-namespaced names.
I hope that helps you with your decision.
Thanks,
Henry
------------------------------------------------------------------
Henry Zongaro XSLT Processors Development
IBM SWS Toronto Lab T/L 969-6044; Phone +1 905 413-6044
mailto:zongaro@(protected)
<br><tt><font size=2>Hello.</font></tt>
<br>
<br><tt><font size=2>"alapati.sasi" <alapati.sasi@(protected)>
wrote on 2007-04-04 02:47:28 PM:<br>
> i need to transform a big source xml into target xml . My source xml
comes<br>
> with the namespace prefix and my xsl doesnt contain any prefixes for
xpath.<br>
> <br>
> its very difficult to change all the xpath's at run time for me .<br>
> <br>
> i have two options<br>
> 1) First change the source xml to another xml file using <br>
</font></tt>
<br><tt><font size=2>[HZ: Removed stylesheet to create copy using
just local names, no namespaces]</font></tt>
<br><tt><font size=2><br>
> this template .This will remove all the prefix bindings .<br>
> Now apply my original style sheet .I Will get the target xml.<br>
> Is this cause me performace hit ? <br>
> Is it better to do like this or Is it better to have local-name()
in the<br>
> stylesheet itself so that there is no additinal transformation required
.<br>
> But if i use local-name() for all the xpath's i heard that processing
time<br>
> will take more time ?<br>
</font></tt>
<br><tt><font size=2>You're right that using a path expression like "*
[local-name()='foo']"
will not perform as well as using the expression "foo" or "p:foo
".
My instinctive reaction is that your other alternative of using a
preprocessing stylesheet that strips out namespaces will probably perform
worse. If the input to a stylesheet is very large, the time spent
constructing the input data model and serializing the result (assuming
that that is about as large) often dominates the performance; in this case,
you would be doing all of that twice. However, it really depends
on your particular XML and XSL. Your best bet would probably be to
prototype both solutions, and see how they perform for your particular.</font><
/tt>
<br>
<br><tt><font size=2>If you're using the SAX API to deliver your XML to
your stylesheet, another option might be to apply some filtering of the
SAX events that removes namespace declarations, and changes element and
attribute names to equivalent, non-namespaced names.</font></tt>
<br>
<br><font size=2 face="sans-serif">I hope that helps you with your decision.<
/font>
<br><font size=2 face="sans-serif"><br>
Thanks,<br>
<br>
Henry<br>
------------------------------------------------------------------<br>
Henry Zongaro XSLT Processors Development<br>
IBM SWS Toronto Lab T/L 969-6044; Phone +1 905 413-6044<br>
mailto:zongaro@(protected)</font>
<br>
|
|
|