Re: [JDBC] Prepared statement performance...

On Fri, 27 Sep 2002, Barry Lind wrote:

> First off I dissagree with your reading of the spec that the statement
> or prepared statement object are only intended for one sql statement.
> If that were true why would you have Statement.getMoreResults()?

Because a single statement can return multiple result sets. Consider
a stored procedure that does several SELECTs, for example.

> The API clearly supports a single statement execute returning multiple
> result sets which implies to me that the single execute can be used for
> multiple individual sql statements chained together.

I'd disagree. Otherwise why would we have a facility for statement batches?

At any rate, I can guarantee you that statement chaning is not portable.

> The uses of the Statement object and PreparedStatement object do not
> IMHO have anything to do with you many times you use them. They have to
> do with how you supply values in the sql statement. If you use just the
> Statement object you are required to know the postgres date format in
> order to include a date value, where it is much easier (and more
> portable across databases) to just use a PreparedStatement, a ?, and a
> setDate() call.

I agree entirely. Even more importantly, it's much, much more difficult
to write a secure application (one not subject to SQL injection attacks)
if you are forced to quote data yourself. The driver already knows how
to deal with any string you pass to it; why would you want to re-write
that code, possibily introducing errors into it? (For those not familiar
with SQL injection attacks, I'm referring to the situation where someone
types, say, "foo'; DROP TABLE bar;" into the "Name" field on your web
form, or whatever.)

cjs
--
Curt Sampson <cjs(at)cynic(dot)net> +81 90 7737 2974 http://www.netbsd.org
Don't you know, in this new Dark Age, we're all light. --XTC