Re: JDBC Style

["Dan Hoover" <dan@xxxxxxxxxxxxx>]

Here is a link to the java2 1.3.1 platform sdk documentation on resultsets.
http://java.sun.com/j2se/1.3/docs/api/java/sql/ResultSet.html

As stated you can
    rs.previous()
    rs.next()
    rs.first()
    rs.last()

    and so on.

In VB you do have the ability with recordsets to do the following:
if rs.bof and rs.eof then 'this will check if the recordset actually has
data without moving the cursor

Unfortunately there is no equivalent in java to bof or eof.
However if you:
ResultSet rs = stmt.ExecuteQuery("Select * from table") ;

if ( !rs.next() )
    // no rows found
else
    do    {
    // a row was found and process
    } while ( rs.next() )

One possible workaround.

BTW the same logic scenario here is the same as embedded SQL in RPG.  You
must declare a cursor, open the cursor and then fetch the cursor.  If sqlcod
= 100 then no rows are retrieved

c/exec sql
 + declare @c1 cursor for select * from table
c/end-exec

c/exec sql open @c1
c/end-exec

c/exec sql fetch @c1 into :cursorvar
c/end-exec

c                        if         sqlcod <> 0
c*  no rows found or error
c                        endif

c                        dow    sqlcod = 0
 * logic for processing rows
c/exec sql fetch @c1 into :cursorvar
c/end-exec
c                        enddo

...
HTH
Dan

----- Original Message -----
From: "Price, Chris" <chris_price@nsb.co.uk>
To: <java400-l@midrange.com>
Sent: Tuesday, November 27, 2001 9:34 AM
Subject: RE: JDBC Style


> This message is in MIME format. Since your mail reader does not understand
> this format, some or all of this message may not be legible.
> --
> [ Picked text/plain from multipart/alternative ]
> Thanks for the answer Dan.
>
> The "problem" I have with using next() to determine if a record set is
empty
> , is that it moves the file pointer (oops - betraying my RPG origins now)
I
> mean cursor, so the result set is changed. I know I can move it back
again,
> but this seems a bit sloppy to me, hence my post.
>
> The problem may well of course be mine, I'm that I'm still thinking like
an
> RPG programmer and want to know why I can't have my file indicators
> back....(VBG)
>
> Chris
>
> -----Original Message-----
> From: Dan Hoover [mailto:dan@hooversys.com]
> Sent: 27 November 2001 14:20
> To: java400-l@midrange.com
> Subject: Re: JDBC Style
>
>
> if (!rs.next() ) {}
>
> HTH
> Dan
> ----- Original Message -----
> From: "Price, Chris" <chris_price@nsb.co.uk>
> To: <java400-l@midrange.com>
> Sent: Tuesday, November 27, 2001 9:11 AM
> Subject: JDBC Style
>
>
> > This message is in MIME format. Since your mail reader does not
understand
> > this format, some or all of this message may not be legible.
> > --
> > [ Picked text/plain from multipart/alternative ]
> > All,
> >
> > What the best (most elegant, most efficient) way to determine if a JBDC
> > Result Set is empty?
> >
> > Chris
> >
> >
> >
> > _______________________________________________
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> >
>
>
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