to plan nodes, not vice-versa.  All executor state nodes now inherit from
struct PlanState.  Copying of plan trees has been simplified by not
storing a list of SubPlans in Plan nodes (eliminating duplicate links).
The executor still needs such a list, but it can build it during
ExecutorStart since it has to scan the plan tree anyway.
No initdb forced since no stored-on-disk structures changed, but you
will need a full recompile because of node-numbering changes.

to MemSet is a performance boost.

command status at the interactive level.  SPI_processed, etc are set
in the same way as the returned command status would have been set if
the same querystring were issued interactively.  Per gripe from
Michael Paesold 25-Sep-02.

(overlaying low byte of page size) and add HEAP_HASOID bit to t_infomask,
per earlier discussion.  Simplify scheme for overlaying fields in tuple
header (no need for cmax to live in more than one place).  Don't try to
clear infomask status bits in tqual.c --- not safe to do it there.  Don't
try to force output table of a SELECT INTO to have OIDs, either.  Get rid
of unnecessarily complex three-state scheme for TupleDesc.tdhasoids, which
has already caused one recent failure.  Improve documentation.

bitmap, if present).

Per Tom Lane's suggestion the information whether a tuple has an oid
or not is carried in the tuple descriptor.  For debugging reasons
tdhasoid is of type char, not bool.  There are predefined values for
WITHOID, WITHOUTOID and UNDEFOID.

This patch has been generated against a cvs snapshot from last week
and I don't expect it to apply cleanly to current sources.  While I
post it here for public review, I'm working on a new version against a
current snapshot.  (There's been heavy activity recently; hope to
catch up some day ...)

This is a long patch;  if it is too hard to swallow, I can provide it
in smaller pieces:

Part 1:  Accessor macros
Part 2:  tdhasoid in TupDesc
Part 3:  Regression test
Part 4:  Parameter withoid to heap_addheader
Part 5:  Eliminate t_oid from HeapTupleHeader

Part 2 is the most hairy part because of changes in the executor and
even in the parser;  the other parts are straightforward.

Up to part 4 the patched postmaster stays binary compatible to
databases created with an unpatched version.  Part 5 is small (100
lines) and finally breaks compatibility.

Manfred Koizar

in snapshots, per my proposal of a few days ago.  Also, tweak heapam.c
routines (heap_insert, heap_update, heap_delete, heap_mark4update) to
be passed the command ID to use, instead of doing GetCurrentCommandID.
For catalog updates they'll still get passed current command ID, but
for updates generated from the main executor they'll get passed the
command ID saved in the snapshot the query is using.  This should fix
some corner cases associated with functions and triggers that advance
current command ID while an outer query is still in progress.

have been divided according to the type of object manipulated - so ALTER
TABLE code is in tablecmds.c, aggregate commands in aggregatecmds.c and
so on.

A few common support routines remain in define.c (prototypes in
src/include/commands/defrem.h).

No code has been changed except for includes to reflect the new files.
The prototypes for aggregatecmds.c, functioncmds.c, operatorcmds.c,
and typecmds.c remain in src/include/commands/defrem.h.

From John Gray <jgray@azuli.co.uk>

the parsetree representation.  As yet we don't *do* anything with schema
names, just drop 'em on the floor; but you can enter schema-compatible
command syntax, and there's even a primitive CREATE SCHEMA command.
No doc updates yet, except to note that you can now extract a field
from a function-returning-row's result with (foo(...)).fieldname.

are now both invoked once per received SQL command (raw parsetree) from
pg_exec_query_string.  BeginCommand is actually just an empty routine
at the moment --- all its former operations have been pushed into tuple
receiver setup routines in printtup.c.  This makes for a clean distinction
between BeginCommand/EndCommand (once per command) and the tuple receiver
setup/teardown routines (once per ExecutorRun call), whereas the old code
was quite ad hoc.  Along the way, clean up the calling conventions for
ExecutorRun a little bit.

report for each received SQL command, regardless of rewriting activity.
Also ensure that this report comes from the 'original' command, not the
last command generated by rewrite; this fixes 7.2 breakage for INSERT
commands that have actions added by rules.  Fernando Nasser and Tom Lane.

originally created with, so that the set of visible tuples does not
change as a result of other activity.  This essentially makes PG cursors
INSENSITIVE per the SQL92 definition.  See bug report of 13-Feb-02.

portal's memory context, so that they will live as long as the portal does.

is gone, usage messages now go through elog(DEBUG).

Need to return a TupleTableSlot, not just a bare tuple.

tests pass.

user columns.  Needed for foreign keys on OID, but useful in general.

readability.  Bizarre '(long *) TRUE' return convention is gone,
in favor of just raising an error internally in dynahash.c when
we detect hashtable corruption.  HashTableWalk is gone, in favor
of using hash_seq_search directly, since it had no hope of working
with non-LONGALIGNable datatypes.  Simplify some other code that was
made undesirably grotty by promixity to HashTableWalk.

it copies the tupdesc into upper-executor memory.  This is necessary
for returning tuple descriptors without leaking all of lower exec memory.

- New functions to create a portal using a prepared/saved
  SPI plan or lookup an existing portal by name.
- Functions to fetch/move from/in portals. Results are placed
  in the usual SPI_processed and SPI_tuptable, so the entire
  set of utility functions can be used to gain attribute access.
- Prepared/saved SPI plans now use their own memory context
  and SPI_freeplan(plan) can remove them.
- Tuple result sets (SPI_tuptable) now uses it's own memory
  context and can be free'd by SPI_freetuptable(tuptab).

Enhancement of PL/pgSQL

- Uses generic named portals internally in FOR ... SELECT
  loops to avoid running out of memory on huge result sets.
- Support for CURSOR and REFCURSOR syntax using the new SPI
  functionality. Cursors used internally only need no explicit
  transaction block. Refcursor variables can be used inside
  of explicit transaction block to pass cursors between main
  application and functions.


Jan

syntax.  Fix the RESULT_OID case, which never worked.  Add documentation.

used before ...

leak memory when printing a toasted attribute, and printtup_internal
didn't work at all...

maintained for each cache entry.  A cache entry will not be freed until
the matching ReleaseSysCache call has been executed.  This eliminates
worries about cache entries getting dropped while still in use.  See
my posting to pg-hackers of even date for more info.

ExecutorRun.  This allows LIMIT to work in a view.  Also, LIMIT in a
cursor declaration will behave in a reasonable fashion, whereas before
it was overridden by the FETCH count.

for details).  It doesn't really do that much yet, since there are no
short-term memory contexts in the executor, but the infrastructure is
in place and long-term contexts are handled reasonably.  A few long-
standing bugs have been fixed, such as 'VACUUM; anything' in a single
query string crashing.  Also, out-of-memory is now considered a
recoverable ERROR, not FATAL.
Eliminate a large amount of crufty, now-dead code in and around
memory management.
Fix problem with holding off SIGTRAP, SIGSEGV, etc in postmaster and
backend startup.

fmgr_faddr() in favor of new-style calls.  Lots of cleanup of
sloppy casts to use XXXGetDatum and DatumGetXXX ...

would crash, due to premature invocation of SetQuerySnapshot().  Clean
up problems with handling of multiple queries by splitting
pg_parse_and_plan into two routines.  The old code would not, for
example, do the right thing with END; SELECT... submitted in one query
string when it had been in transaction abort state, because it'd decide
to skip planning the SELECT before it had executed the END.  New
arrangement is simpler and doesn't force caller to plan if only
parse+rewrite is needed.

Jan

Make all system indexes unique.
Make all cache loads use system indexes.
Rename *rel to *relid in inheritance tables.
Rename cache names to be clearer.

Fewer calls to nameout.

Better use of RelationGetRelationName.