last nextval() or setval() performed by the current session. Update the
docs, add regression tests, and bump the catalog version. Patch from
Dennis Björklund, various improvements by Neil Conway.

This allows the result of executing a SELECT to be assigned to a row
variable, record variable, or list of scalars. Docs and regression tests
updated. Per Pavel Stehule, improvements and cleanup by Neil Conway.

<   all temporary tables, removal of any NOTIFYs, cursors, prepared
<   queries(?), currval()s, etc.  This could be used for connection pooling.
<   We could also change RESET ALL to have this functionality.
>   temporary tables, removing any NOTIFYs, cursors, open transactions,
>   prepared queries, currval()s, etc.  This could be used  for connection
>   pooling.  We could also change RESET ALL to have this functionality.
>   The difficult of this features is allowing RESET ALL to not affect
>   changes made by the interface driver for its internal use.  One idea is
>   for this to be a protocol-only feature.  Another approach is to notify
>   the protocol when a RESET CONNECTION command is used.

```------------------------------------------------------------------------
While playing around, I got the following error message:

--
FATAL:  pre-existing shared memory block (key 5432001, ID 90898435) is
still in use
HINT:  If you're sure there are no old server processes still running,
remove the shared memory block with the command "ipcrm", or just delete
the file "/home/hlinnaka/pgsql/data/postmaster.pid".
```

Thats normal because I used "kill -9 postmaster" to shut down.

The hint advises me to use "ipcrm", but there's the "ipcclean" script in
bin for just this purpose. The hint should probably advise to use
ipcclean.

The attached patch replaces all occurances of "ipcrm" with "ipcclean" in
src/backend/utils/init/miscinit.c and all the translations in
src/backend/po.

While reviewing the patch, I noticed a likely typo in hr.po. While I
don't
speak Croatian, the translation seems to advise to use the "icpm(1)"
command. I changed that to "ipcclean" too.

Heikki Linnakangas

> * Fix incorrect rtree results due to wrong assumptions about "over"
>   operator semantics [rtree]

up have the standard layout with unused space between pd_lower and pd_upper.
When this is set, XLogInsert will omit the unused space without bothering
to scan it to see if it's zero.  That saves time in XLogInsert, and also
allows reversion of my earlier patch to make PageRepairFragmentation et al
explicitly re-zero freed space.  Per suggestion by Heikki Linnakangas.

That code is never going to be used in the foreseeable future, and
where it's more than a stub it's making the redo routines harder to
read.

Laszlo Hornyak

other_rel_list with a single array indexed by rangetable index.
This reduces find_base_rel from O(N) to O(1) without any real penalty.
While find_base_rel isn't one of the major bottlenecks in any profile
I've seen so far, it was starting to creep up on the radar screen
for complex queries --- so might as well fix it.

a new PlannerInfo struct, which is passed around instead of the bare
Query in all the planning code.  This commit is essentially just a
code-beautification exercise, but it does open the door to making
larger changes to the planner data structures without having to muck
with the widely-known Query struct.

<   cleaned up properly.  A new signal is needed for safe termination.
>   cleaned up properly.  A new signal is needed for safe termination
>   because backends must first do a query cancel, then exit once they
>   have run the query cancel cleanup routine.

1. Rename spi_return_next to return_next.
2. Add a new test for return_next.
3. Update the expected output.
4. Update the documentation.

Abhijit Menon-Sen

prepared for HAVE_INT64_TIMESTAMP.  Per report from Guillaume Beaudoin.

> * Add two-phase commit [2phase]

representation as the jointree) with two lists of RTEs, one showing
the RTEs accessible by qualified names, and the other showing the RTEs
accessible by unqualified names.  I think this is conceptually simpler
than what we did before, and it's sure a whole lot easier to search.
This seems to eliminate the parse-time bottleneck for deeply nested
JOIN structures that was exhibited by phil@vodafone.

<   logs
>   logs [pitr]
130c130
< * Allow a warm standby system to also allow read-only queries
> * Allow a warm standby system to also allow read-only queries [pitr]

<   information, either zone name or offset from UTC
>   information, either zone name or offset from UTC [timezone]

> * Allow major upgrades without dump/reload, perhaps using pg_upgrade
>   [pg_upgrade]

---------------------------------------------------------------------------

Tom Lane <tgl@sss.pgh.pa.us> writes:
> a_ogawa <a_ogawa@hi-ho.ne.jp> writes:
> > It is a reasonable idea. However, the majority part of MemSet was not
> > able to be avoided by this idea. Because the per-tuple contexts are used
> > at the early stage of executor.
>
> Drat.  Well, what about changing that?  We could introduce additional
> contexts or change the startup behavior so that the ones that are
> frequently reset don't have any data in them unless you are working
> with pass-by-ref values inside the inner loop.

That might be possible. However, I think that we should change only
aset.c about this article.
I thought further: We can check whether context was used from the last
reset even when blocks list is not empty. Please see attached patch.

Allow kerberos name and username case sensitivity to be specified from
postgresql.conf.

---------------------------------------------------------------------------


Here's an updated version of the patch, with the following changes:

1) No longer uses "service name" as "application version". It's instead
hardcoded as "postgres". It could be argued that this part should be
backpatched to 8.0, but it doesn't make a big difference until you can
start changing it with GUC / connection parameters. This change only
affects kerberos 5, not 4.

2) Now downcases kerberos usernames when the client is running on win32.

3) Adds guc option for "krb_caseins_users" to make the server ignore
case mismatch which is required by some KDCs such as Active Directory.
Off by default, per discussion with Tom. This change only affects
kerberos 5, not 4.

4) Updated so it doesn't conflict with the rendevouz/bonjour patch
already in ;-)

Magnus Hagander

>
> > The second issue is where plperl returns a large result set.

I have attached the following seven patches to address this problem:

1. Trivial. Replaces some errant spaces with tabs.

2. Trivial. Fixes the spelling of Jan's name, and gets rid of many
   inane, useless, annoying, and often misleading comments. Here's
   a sample: "plperl_init_all() - Initialize all".

   (I have tried to add some useful comments here and there, and will
   continue to do so now and again.)

3. Trivial. Splits up some long lines.

4. Converts SRFs in PL/Perl to use a Tuplestore and SFRM_Materialize
   to return the result set, based on the PL/PgSQL model.

   There are two major consequences: result sets will spill to disk when
   they can no longer fit in work_mem; and "select foo_srf()" no longer
   works. (I didn't lose sleep over the latter, since that form is not
   valid in PL/PgSQL, and it's not documented in PL/Perl.)

5. Trivial, but important. Fixes use of "undef" instead of undef. This
   would cause empty functions to fail in bizarre ways. I suspect that
   there's still another (old) bug here. I'll investigate further.

6. Moves the majority of (4) out into a new plperl_return_next()
   function, to make it possible to expose the functionality to
   Perl; cleans up some of the code besides.

7. Add an spi_return_next function for use in Perl code.

If you want to apply the patches and try them out, 8-composite.diff is
what you should use. (Note: my patches depend upon Andrew's use-strict
and %_SHARED patches being applied.)

Here's something to try:

    create or replace function foo() returns setof record as $$
    $i = 0;
    for ("World", "PostgreSQL", "PL/Perl") {
        spi_return_next({f1=>++$i, f2=>'Hello', f3=>$_});
    }
    return;
    $$ language plperl;
    select * from foo() as (f1 integer, f2 text, f3 text);

(Many thanks to Andrews Dunstan and Supernews for their help.)

Abhijit Menon-Sen

> a_ogawa <a_ogawa@hi-ho.ne.jp> writes:
> > It is a reasonable idea. However, the majority part of MemSet was not
> > able to be avoided by this idea. Because the per-tuple contexts are used
> > at the early stage of executor.
>
> Drat.  Well, what about changing that?  We could introduce additional
> contexts or change the startup behavior so that the ones that are
> frequently reset don't have any data in them unless you are working
> with pass-by-ref values inside the inner loop.

That might be possible. However, I think that we should change only
aset.c about this article.
I thought further: We can check whether context was used from the last
reset even when blocks list is not empty. Please see attached patch.

The effect of the patch that I measured is as follows:

o Execution time that executed the SQL ten times.
(1)Linux(CPU: Pentium III, Compiler option: -O2)
 - original: 24.960s
 - patched : 23.114s

(2)Linux(CPU: Pentium 4, Compiler option: -O2)
 - original: 8.730s
 - patched : 7.962s

(3)Solaris(CPU: Ultra SPARC III, Compiler option: -O2)
 - original: 37.0s
 - patched : 33.7s

Atsushi Ogawa (a_ogawa)

RTE of interest, rather than the whole rangetable list.  This makes
the API more understandable and avoids duplicate RTE lookups.  This
patch reverts no-longer-needed portions of my patch of 2004-08-19.

> * Allow pg_ctl to work properly with configuration files located outside
>   the PGDATA directory
>
>   pg_ctl can not read the pid file because it isn't located in the
>   config directory but in the PGDATA directory.  The solution is to
>   allow pg_ctl to read and understand postgresql.conf to find the
>   data_directory value.
>

>
>   O_DIRECT doesn't have the same media write guarantees as fsync, so it
>   is in addition to the fsync method, not in place of it.
>

Division rounding was causing incorrect results.  Test case:

	test=> SELECT 12345678901234567890 % 123;
	 ?column?
	----------
	       78
	(1 row)

Was returning -45.

Weiping (Laser)

accordingly (this field was always initialized to true). Patch from
Alvaro Herrera.

performance problem pointed out by phil@vodafone: to wit, we were
spending O(N^2) time to check dropped-ness in an N-deep join tree,
even in the case where the tree was freshly constructed and couldn't
possibly mention any dropped columns.  Instead of recursing in
get_rte_attribute_is_dropped(), change the data structure definition:
the joinaliasvars list of a JOIN RTE must have a NULL Const instead
of a Var at any position that references a now-dropped column.  This
costs nothing during normal parse-rewrite-plan path, and instead we
have a linear-time update to make when loading a stored rule that
might contain now-dropped columns.  While at it, move the responsibility
for acquring locks on relations referenced by rules into this separate
function (which I therefore chose to call AcquireRewriteLocks).
This saves effort --- namely, duplicated lock grabs in parser and rewriter
--- in the normal path at a cost of one extra non-locked heap_open()
in the stored-rule path; seems a good tradeoff.  A fringe benefit is
that it is now *much* clearer that we acquire lock on relations referenced
in rules before we make any rewriter decisions based on their properties.
(I don't know of any bug of that ilk, but it wasn't exactly clear before.)