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From Dominik Jednoralski <twelv...@googlemail.com>
Subject Re: Strange SQLException when trying to read existing row
Date Mon, 17 Aug 2009 15:26:33 GMT
Hi Sai,

many thanks for your response. Actually, I polished the code before
publishing to the mailing list. My original code at the position of the
error looked like this

*if (result != null) {
**                if (result.next()) {**
                // breaks with sql-exception: no such row
                String data = result.getString(1);*

result.next() at this position always reports an empty ResultSet.

Best

Dominik


2009/8/17 Sai Pullabhotla <sai.pullabhotla@jmethods.com>

> When a ResultSet is produced, the cursor is positioned before the
> first row. You must call ResultSet.next() method to move the cursor to
> the first row and then the ResultSet.getXXX methods for each column.
> Can you verify/confirm if your code is setup to do this?
>
> Thanks.
>
> Sai Pullabhotla
> www.jMethods.com
>
>
>
>
> On Sun, Aug 16, 2009 at 5:04 PM, Dominik
> Jednoralski<twelve02@googlemail.com> wrote:
> > Hi Geeks,
> >
> > I'm integrating the derby-database into a JAVA-driven web application.
> I'm
> > new to derby and I have a problem with the execution of a
> SELECT-statement.
> > The returned ResultSet is empty, although the selected row is definitely
> > stored.
> >
> > The code below works, creates a new table and inserts a dummy row.
> >
> > CREATE TABLE gaps (gapId int generated by default as identity,
> > MBaseId VARCHAR(256), important INTEGER DEFAULT 0,
> > ignore INTEGER DEFAULT 0, data LONG VARCHAR,
> > creation TIMESTAMP, lastModified TIMESTAMP)
> > INSERT INTO gaps (data) VALUES ('foo')
> >
> > At this position, the row is accessible and everything is fine. Later,
> when
> > I want to retrieve this very row via the follwing code, it breaks because
> > the ResultSet is empty. The methods are both members of the same class
> and
> > share the connection and statement, which both are class members.
> >
> >  ResultSet result = statement.executeQuery("SELECT data "
> >                         + "FROM gaps WHERE gapId = 1" );
> >
> >             if (result != null) {
> >
> >                 // breaks with sql-exception: no such row
> >                 String data = result.getString(1);
> >
> >
> > Can anyone of you help me with this? I'm pretty confused. Thanks a lot in
> > advance =)
> >
> > best
> >
> > Dominik
>

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