2. Get rid of locking when updating statistics in vacuum.
3. Use QuerySnapshot in COPY TO and call SetQuerySnashot
   in main tcop loop before FETCH and COPY TO.

from being accepted when they are passed from client connection request.
Get rid of a couple that no longer do anything (like -P).

lists are now plain old garden-variety Lists, allocated with palloc,
rather than specialized expansible-array data allocated with malloc.
This substantially simplifies their handling and eliminates several
sources of memory leakage.
Several basic types of erroneous queries (syntax error, attempt to
insert a duplicate key into a unique index) now demonstrably leak
zero bytes per query.

-d4 now prints compressed trees from nodeToString()
-d5 prints pretty trees via nodeDisplay()

new pg_options: pretty_plan, pretty_parse, pretty_rewritten

Jan

on queries involving UNION, EXCEPT, INTERSECT.

been applied. The patches are in the .tar.gz attachment at the end:

varchar-array.patch     this patch adds support for arrays of bpchar() and
                        varchar(), which where always missing from postgres.

                        These datatypes can be used to replace the _char4,
                        _char8, etc., which were dropped some time ago.

block-size.patch        this patch fixes many errors in the parser and other
                        program which happen with very large query statements
                        (> 8K) when using a page size larger than 8192.

                        This patch is needed if you want to submit queries
                        larger than 8K. Postgres supports tuples up to 32K
                        but you can't insert them because you can't submit
                        queries larger than 8K. My patch fixes this problem.

                        The patch also replaces all the occurrences of `8192'
                        and `1<<13' in the sources with the proper constants
                        defined in include files. You should now never find
                        8192 hardwired in C code, just to make code clearer.


--
Massimo Dal Zotto

can be generated in a buffer and then sent to the frontend in a single
libpq call.  This solves problems with NOTICE and ERROR messages generated
in the middle of a data message or COPY OUT operation.

instead of doing a kill(self, SIGQUIT) and expecting the signal handler
to do it.  Also, clean up inconsistent definitions of the sigjmp buffer
in the several files that already referenced it.

I have solved some problems with dynamic loading on NT. It is possible
to
run succesfully both trigger and plpgsql regression tests. The patch is
in
the included file "diff".

                        Dan

From: Tatsuo Ishii <t-ishii@sra.co.jp>

Ok. I made patches replacing all of "#if FALSE" or "#if 0" to "#ifdef
NOT_USED" for current. I have tested these patches in that the
postgres binaries are identical.

INTERSECT and EXCEPT is available for postgresql-v6.4!

The patch against v6.4 is included at the end of the current text
(in uuencoded form!)

I also included the text of my Master's Thesis. (a postscript
version). I hope that you find something of it useful and would be
happy if parts of it find their way into the PostgreSQL documentation
project (If so, tell me, then I send the sources of the document!)

The contents of the document are:
  -) The first chapter might be of less interest as it gives only an
     overview on SQL.

  -) The second chapter gives a description on much of PostgreSQL's
     features (like user defined types etc. and how to use these features)

  -) The third chapter starts with an overview of PostgreSQL's internal
     structure with focus on the stages a query has to pass (i.e. parser,
     planner/optimizer, executor). Then a detailed description of the
     implementation of the Having clause and the Intersect/Except logic is
     given.

Originally I worked on v6.3.2 but never found time enough to prepare
and post a patch. Now I applied the changes to v6.4 to get Intersect
and Except working with the new version. Chapter 3 of my documentation
deals with the changes against v6.3.2, so keep that in mind when
comparing the parts of the code printed there with the patched sources
of v6.4.

Here are some remarks on the patch. There are some things that have
still to be done but at the moment I don't have time to do them
myself. (I'm doing my military service at the moment) Sorry for that
:-(

-) I used a rewrite technique for the implementation of the Except/Intersect
   logic which rewrites the query to a semantically equivalent query before
   it is handed to the rewrite system (for views, rules etc.), planner,
   executor etc.

-) In v6.3.2 the types of the attributes of two select statements
   connected by the UNION keyword had to match 100%. In v6.4 the types
   only need to be familiar (i.e. int and float can be mixed). Since this
   feature did not exist when I worked on Intersect/Except it
   does not work correctly for Except/Intersect queries WHEN USED IN
   COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the
   resulting table. This is because until now the types of the attributes of
   the first select statement have been used for the resulting table.
   When Intersects and/or Excepts are used in combination with Unions it
   might happen, that the first select statement of the original query
   appears at another position in the query which will be executed. The reason
   for this is the technique used for the implementation of
   Except/Intersect which does a query rewrite!)
   NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT
         queries!!!

-) I had to add the field intersect_clause to some data structures
   but did not find time to implement printfuncs for the new field.
   This does NOT break the debug modes but when an Except/Intersect
   is used the query debug output will be the already rewritten query.

-) Massive changes to the grammar rules for SELECT and INSERT statements
   have been necessary (see comments in gram.y and documentation for
   deatails) in order to be able to use mixed queries like
   (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...;

-) When using UNION/EXCEPT/INTERSECT you will get:
   NOTICE: equal: "Don't know if nodes of type xxx are equal".
   I did not have  time to add comparsion support for all the needed nodes,
   but the default behaviour of the function equal met my requirements.
   I did not dare to supress this message!

   That's the reason why the regression test for union will fail: These
   messages are also included in the union.out file!

-) Somebody of you changed the union_planner() function for v6.4
   (I copied the targetlist to new_tlist and that was removed and
   replaced by a cleanup of the original targetlist). These chnages
   violated some having queries executed against views so I changed
   it back again. I did not have time to examine the differences between the
   two versions but now it works :-)
   If you want to find out, try the file queries/view_having.sql on
   both versions and compare the results . Two queries won't produce a
   correct result with your version.

regards

    Stefan

DataDir is set after read_pg_options if postgres is called
interactively.  If postgres is forked by postgres DataDir is read from
the PGDATA enviromnent variable set by the postmaster and this explains
while the bug disappears.  I have written this patch but I don't like
it. Any better idea?

Massimo Dal Zotto

This is plain wrong, but check to see if DataDir was set *before* running
read_pg_options ... read_pg_options should probably be moved to after the
getopt() instead?

case statement in select call was missing a break...

and possibly other problems.  Minor changes in xact.c and postgres.c's
main loop to support new handling of async NOTIFY.

and what wasn't.  Also try to improve the comments so that doesn't happen
again.  Changed SIGPIPE handling to SIG_IGN so that if frontend quits,
we will finish out the current command and return to main loop before
quitting.  This seems much safer than a forced abort mid-command.

From: Massimo Dal Zotto <dz@cs.unitn.it>

From: Massimo Dal Zotto <dz@cs.unitn.it>

> tprintf.patch
>
>       tprintf.patch
>
>       adds functions and macros which implement a conditional trace package
>       with the ability to change flags and numeric options of running
>       backends at runtime.
>       Options/flags can be specified in the command line and/or read from
>       the file pg_options in the data directory.

From: Massimo Dal Zotto <dz@cs.unitn.it>

assert.patch

        adds a switch to turn on/off the assert checking if enabled at compile
        time. You can now compile postgres with assert checking and disable it
        at runtime in a production environment.

 Formerly came just after early exit from loop for command nodes,
 so missed some cases.

    patch is applied:

	Rewrite rules on relation level work fine now.

	Event qualifications on insert/update/delete  rules  work
	fine now.

	I  added  the  new  keyword  OLD to reference the CURRENT
	tuple. CURRENT will be removed in 6.5.

	Update rules can  reference  NEW  and  OLD  in  the  rule
	qualification and the actions.

	Insert/update/delete rules on views can be established to
	let them behave like real tables.

	For  insert/update/delete  rules  multiple  actions   are
	supported  now.   The  actions  can also be surrounded by
	parantheses to make psql  happy.   Multiple  actions  are
	required if update to a view requires updates to multiple
	tables.

	Regular users  are  permitted  to  create/drop  rules  on
	tables     they     have     RULE     permissions     for
	(DefineQueryRewrite() is  now  able  to  get  around  the
	access  restrictions  on  pg_rewrite).  This enables view
	creation for regular users too. This  required  an  extra
	boolean  parameter  to  pg_parse_and_plan() that tells to
	set skipAcl on all rangetable entries  of  the  resulting
	queries.       There      is      a      new     function
	pg_exec_query_acl_override()  that  could  be   used   by
	backend utilities to use this facility.

	All rule actions (not only views) inherit the permissions
	of the event relations  owner.  Sample:  User  A  creates
	tables    T1    and    T2,   creates   rules   that   log
	INSERT/UPDATE/DELETE on T1 in T2 (like in the  regression
	tests  for rules I created) and grants ALL but RULE on T1
	to user B.  User B  can  now  fully  access  T1  and  the
	logging  happens  in  T2.  But user B cannot access T2 at
	all, only the rule actions can. And due to  missing  RULE
	permissions on T1, user B cannot disable logging.

	Rules  on  the  attribute  level are disabled (they don't
	work properly and since regular users are  now  permitted
	to create rules I decided to disable them).

	Rules  on  select  must have exactly one action that is a
	select (so select rules must be a view definition).

	UPDATE NEW/OLD rules  are  disabled  (still  broken,  but
	triggers can do it).

	There are two new system views (pg_rule and pg_view) that
	show the definition of the rules or views so the db admin
	can  see  what  the  users do. They use two new functions
	pg_get_ruledef() and pg_get_viewdef() that are  builtins.

	The functions pg_get_ruledef() and pg_get_viewdef() could
	be used to implement rule and view support in pg_dump.

	PostgreSQL is now the only database system I  know,  that
	has rewrite rules on the query level. All others (where I
	found a  rule  statement  at  all)  use  stored  database
	procedures  or  the  like  (triggers as we call them) for
	active rules (as some call them).

    Future of the rule system:

	The now disabled parts  of  the  rule  system  (attribute
	level,  multiple  actions on select and update new stuff)
	require a complete new rewrite handler from scratch.  The
	old one is too badly wired up.

	After  6.4  I'll  start to work on a new rewrite handler,
	that fully supports the attribute level  rules,  multiple
	actions on select and update new.  This will be available
	for 6.5 so we get full rewrite rule capabilities.

Jan