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> > The issue is relevant to ad hoc queries but it's moot for
> > repetitive queries
>
> That statement confuses me, and not only because Americans appear to use the
> word "moot" in the opposite of its original English sense of "arguable".
>
> The benefit of a string interface is that it gives looser coupling between
> systems. The benefit of a custom syntax/protocol is that it gives earlier
> validation. The experience of the last few years is that loose coupling
> tends to win, across most application scenarios. Hence XML.
My comment was the argument about "strings or not" is moot (as in "deprived of
practical relevance") when we're talking about stored queries -- as opposed to
ad hoc, single-execution queries.
For single-execution queries, the XQJ client program passes the query string to
the driver for each execution of the query (or the abstract syntax tree
alternative).
For repetitive, stored queries, we don't pass a string each time so we don't
parse the query repetitively. We parse it once, and on subsequent executions of
the query, we pass execution time parameters.
> The benefit of a custom syntax/protocol is that it gives earlier validation.
In the case of [JDBC | XQJ], we can use strings and delegate validation to the
[SQL | XQuery] engine. We can use prepared statements (JDBC) or prepared
expressions (XQJ) as a separate, distinct process before we execute a query.
That gives us pre-execution validation and exception checking. (Pre-execution in
this context is a reference to query execution, not program execution.)
======== Ken North ===========
www.WebServicesSummit.com
www.SQLSummit.com
www.GridSummit.com
----- Original Message -----
From: "Michael Kay" <michael.h.kay@ntlworld.com>
To: "'Ken North'" <kennorth@sbcglobal.net>; <xml-dev@lists.xml.org>
Sent: Tuesday, June 29, 2004 1:21 AM
Subject: RE: [xml-dev] Early Draft Review: XQuery for Java (JSR 225)
>
> > The issue is relevant to ad hoc queries but it's moot for
> > repetitive queries,
> > such as for generating a monthly publication.
>
> That statement confuses me, and not only because Americans appear to use the
> word "moot" in the opposite of its original English sense of "arguable".
>
> The benefit of a string interface is that it gives looser coupling between
> systems. The benefit of a custom syntax/protocol is that it gives earlier
> validation. The experience of the last few years is that loose coupling
> tends to win, across most application scenarios. Hence XML.
>
> Michael Kay
>
>
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