Release of the GCX XQuery EngineQ

[Jonathan Robie]

Marc Van Cappellen wrote:
> As indicated in some other email on this thread, DataDirect XQuery is an
> implementation with both document projection as well as streaming
> capabilities.
>   

In order to be a little more concrete, I talked with Marc about some 
comparisons we did internally between GCX and DataDirect XQuery. I think 
the results fall out roughly as follows:

- Our XMark performance results are broadly similar to those of GCX for 
our currently released software. The upcoming DataDirect XQuery 3.0 will 
be markedly faster in some cases - for instance, for one XMark query, we 
finished more than 100 times faster.

- Our memory usage was similar for many queries, worse for some, and 
better for others.

As Marc indicated, we support both document projection and streaming (as 
described in A. Marian and J. Simeon, "Projecting XML Documents", Proc. 
VLDB 2003, a really cool and useful paper). DataDirect XQuery is a 
complete commercial implementation of XQuery that is optimized not only 
for XML input, but also for relational input, with support for Web 
service calls and XML converters for non-XML formats.

Jonathan