Обсуждение: more improvements to release notes

This patch makes a bunch of improvements to the release notes. I only
modified release.sgml -- HISTORY will need to be regenerated.

I was able to remove almost all of the "Other uncategorized" release
note entries, but left a few that I wasn't sure what to do with. We
should remove this section, and move the remaining entries to other
sections if necessary.

I had a few questions on some of the entries:

What is the following release note entry supposed to mean? "FETCH 0"
doesn't "do nothing", it now fetches the current cursor row. Bruce,
could you clarify this please?

     * MOVE/FETCH 0 now does nothing; return value of MOVE/FETCH 1/0
       varies based on the current offset in the cursor

This entry is plainly wrong:

     * Cause FETCH 1 to return the current cursor row, or zero if at
       beginning/end of cursor, per SQL spec (Bruce)

FETCH 0 is what actually returns the current cursor row, and returning
"zero" when a row value is expected wouldn't make much sense. I've
changed it to just say:

     * Cause FETCH 0 to return the current cursor row, per SQL spec
(Bruce)

If I've missed some of the intent of the original entry, let me know.

These two entries are duplicates, right?

     * Have SHOW DATESTYLE generate output similar to that used by SET
       DATESTYLE (Tom)
     * Change DATESTYLE to output its value in a more common format
(Tom)

I wasn't sure, so I didn't make this change in the patch.

-Neil

Neil Conway wrote:
> This patch makes a bunch of improvements to the release notes. I only
> modified release.sgml -- HISTORY will need to be regenerated.
>
> I was able to remove almost all of the "Other uncategorized" release
> note entries, but left a few that I wasn't sure what to do with. We
> should remove this section, and move the remaining entries to other
> sections if necessary.
>
> I had a few questions on some of the entries:
>
> What is the following release note entry supposed to mean? "FETCH 0"
> doesn't "do nothing", it now fetches the current cursor row. Bruce,
> could you clarify this please?
>
>      * MOVE/FETCH 0 now does nothing; return value of MOVE/FETCH 1/0
>        varies based on the current offset in the cursor

We had MOVE/FETCH 0 handling that didn't match the SQL spec.  MOVE 0 used
to go to the end of the cursor, and FETCH 0 would return the entire
cursor.  We were basically using 0 to mean ALL, which was clearly wrong.


> This entry is plainly wrong:
>
>      * Cause FETCH 1 to return the current cursor row, or zero if at
>        beginning/end of cursor, per SQL spec (Bruce)

This should read, I think:

>      * Cause FETCH 1 to return the current cursor row number, or zero if at
                                                        ------
>        beginning/end of cursor, per SQL spec (Bruce)

>
> FETCH 0 is what actually returns the current cursor row, and returning
> "zero" when a row value is expected wouldn't make much sense. I've
> changed it to just say:
>
>      * Cause FETCH 0 to return the current cursor row, per SQL spec
> (Bruce)
>
> If I've missed some of the intent of the original entry, let me know.

I have adjusted this in your patch, but we can continue to work on it.

> These two entries are duplicates, right?
>
>      * Have SHOW DATESTYLE generate output similar to that used by SET
>        DATESTYLE (Tom)
>      * Change DATESTYLE to output its value in a more common format
> (Tom)

Yes, I think so.

> I wasn't sure, so I didn't make this change in the patch.

I removed the duplicate.


Patch applied with minor FETCH adjustment.  We will have to revisit
this.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Neil Conway wrote:
> This entry is plainly wrong:
>
>      * Cause FETCH 1 to return the current cursor row, or zero if at
>        beginning/end of cursor, per SQL spec (Bruce)
>
> FETCH 0 is what actually returns the current cursor row, and returning
> "zero" when a row value is expected wouldn't make much sense. I've
> changed it to just say:

I now see where I was wrong.  It should be:

>      * Cause FETCH 1 to return the next cursor row, or zero if at
                                     ----
>        beginning/end of cursor, per SQL spec (Bruce)

Updated.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

On Wed, 2003-10-22 at 13:26, Bruce Momjian wrote:
> >      * Cause FETCH 1 to return the next cursor row, or zero if at
>                                      ----
> >        beginning/end of cursor, per SQL spec (Bruce)

That's better, but still wrong: what does it mean for FETCH 1 to "return
zero if at the beginning/end of cursor"? If we're at the end of the
cursor, we return an empty result set, not "zero".

-Neil

Neil Conway wrote:
> On Wed, 2003-10-22 at 13:26, Bruce Momjian wrote:
> > >      * Cause FETCH 1 to return the next cursor row, or zero if at
> >                                      ----
> > >        beginning/end of cursor, per SQL spec (Bruce)
>
> That's better, but still wrong: what does it mean for FETCH 1 to "return
> zero if at the beginning/end of cursor"? If we're at the end of the
> cursor, we return an empty result set, not "zero".

Yes, it is mixing the return row with the return value of zero --- hence
we need to revisit this.  I can't even remember how this is different
from 7.3.  I remember applying these changes at the direction of others,
and not fully understanding all the issues.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Neil Conway wrote:
> On Wed, 2003-10-22 at 13:26, Bruce Momjian wrote:
> > >      * Cause FETCH 1 to return the next cursor row, or zero if at
> >                                      ----
> > >        beginning/end of cursor, per SQL spec (Bruce)
>
> That's better, but still wrong: what does it mean for FETCH 1 to "return
> zero if at the beginning/end of cursor"? If we're at the end of the
> cursor, we return an empty result set, not "zero".
>

OK, updated:

    <listitem><para>Make MOVE/FETCH 0 now does nothing
       (Bruce)</para></listitem>
    <listitem><para>Cause MOVE/FETCH now returns the number of rows
    moved/fetched, or zero if at the beginning/end of cursor,
       per SQL spec (Bruce)</para></listitem>

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

On Sun, 2003-10-26 at 00:50, Bruce Momjian wrote:
>     <listitem><para>Make MOVE/FETCH 0 now does nothing
>        (Bruce)</para></listitem>

Still wrong :-) "Make ... now does nothing" is ungrammatical.

The other modified entry is incorrect for the same reason ("Cause ...
now returns").

-Neil

Neil Conway wrote:
> On Sun, 2003-10-26 at 00:50, Bruce Momjian wrote:
> >     <listitem><para>Make MOVE/FETCH 0 now does nothing
> >        (Bruce)</para></listitem>
>
> Still wrong :-) "Make ... now does nothing" is ungrammatical.
>
> The other modified entry is incorrect for the same reason ("Cause ...
> now returns").

Fixed --- should be OK now.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073