to ensure that we have released buffer refcounts and so forth, rather than
putting ad-hoc operations before (some of the calls to) proc_exit. Add
commentary to discourage future hackers from repeating that mistake.
in pghackers list. Support for oldstyle internal functions is gone
(no longer needed, since conversion is complete) and pg_language entry
'internal' now implies newstyle call convention. pg_language entry
'newC' is gone; both old and newstyle dynamically loaded C functions
are now called language 'C'. A newstyle function must be identified
by an associated info routine. See src/backend/utils/fmgr/README.
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.
(WAL logging for this is not done yet, however.) Clean up a number of really
crufty things that are no longer needed now that DROP behaves nicely. Make
temp table mapper do the right things when drop or rename affecting a temp
table is rolled back. Also, remove "relation modified while in use" error
check, in favor of locking tables at first reference and holding that lock
throughout the statement.
user is now defined in terms of the user id, the user name is only computed
upon request (for display purposes). This is kind of the opposite of the
previous state, which would maintain the user name and compute the user id
for permission checks.
Besides perhaps saving a few cycles (integer vs string), this now creates a
single point of attack for changing the user id during a connection, for
purposes of "setuid" functions, etc.
including utility statements. Still can't copy or compare executor
state, but at present that doesn't seem to be necessary. This makes
it possible to execute most (all?) utility statements in plpgsql.
Had to change parsetree representation of CreateTrigStmt so that it
contained only legal Nodes, and not bare string constants.
These two routines will now ALWAYS elog() on failure, whether you ask for
a lock or not. If you really want to get a NULL return on failure, call
the new routines heap_open_nofail()/heap_openr_nofail(). By my count there
are only about three places that actually want that behavior. There were
rather more than three places that were missing the check they needed to
make under the old convention :-(.
I did not force. I marked numeric as compressable-but-not-move-off-able,
partly to test that storage mode and partly because I've got doubts
that numerics are large enough to need external storage.
entry that has rules. This allows us to release the rule parsetrees
on relcache flush without needing a working freeObject() routine.
Formerly, the rule trees were leaked permanently at relcache flush.
Also, clean up handling of rule creation and deletion --- there was
not sufficient locking of the relation being modified, and there was
no reliable notification of other backends that a relcache reload
was needed. Also, clean up relcache.c code so that scans of system
tables needed to load a relcache entry are done in the caller's
memory context, not in CacheMemoryContext. This prevents any
un-pfreed memory from those scans from becoming a permanent memory
leak.
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.
key call sites are changed, but most called functions are still oldstyle.
An exception is that the PL managers are updated (so, for example, NULL
handling now behaves as expected in plperl and plpgsql functions).
NOTE initdb is forced due to added column in pg_proc.
a switch statement that has an empty default label. A label of a
switch statement must be followed by a statement (or a label which
is followed by a statement (or a label which ...)).
3. Files include stringinfo.h failed to compile. The macro,
'appendStringInfoCharMacro' is implemented with a '?:' operation
that returns a void expression for the true part and a char expresion
for the false part. Both the true and false parts of the '?:' oper-
ator must return the same type.
Billy G. Allie
Added constraint dumping capability to pg_dump (also from Stephan)
Fixed DROP TABLE -> RelationBuildTriggers: 2 record(s) not found for rel
error.
Fixed little error in gram.y I made the last days.
Jan
syscache and relcache flushes). Relcache entry rebuild now preserves
original tupledesc, rewrite rules, and triggers if possible, so that pointers
to these things remain valid --- if these things change while relcache entry
has positive refcount, we elog(ERROR) to avoid later crash. Arrange for
xact-local rels to be rebuilt when an SI inval message is seen for them,
so that they are updated by CommandCounterIncrement the same as regular rels.
(This is useful because of Hiroshi's recent changes to process our own SI
messages at CommandCounterIncrement time.) This allows simplification of
some routines that previously hacked around the lack of an automatic update.
catcache now keeps its own copy of tupledesc for its relation, rather than
depending on the relcache's copy; this avoids needing to reinitialize catcache
during a cache flush, which saves some cycles and eliminates nasty circularity
problems that occur if a cache flush happens while trying to initialize a
catcache.
Eliminate a number of permanent memory leaks that used to happen during
catcache or relcache flush; not least of which was that catcache never
freed any cached tuples! (Rule parsetree storage is still leaked, however;
will fix that separately.)
Nothing done yet about code that uses tuples retrieved by SearchSysCache
for longer than is safe.
relcache entry no longer leaks a small amount of memory. index_endscan
now releases all the memory acquired by index_beginscan, so callers of it
should NOT pfree the scan descriptor anymore.
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.
The following patch extends the COMMENT ON functionality to the
rest of the database objects beyond just tables, columns, and views. The
grammer of the COMMENT ON statement now looks like:
COMMENT ON [
[ DATABASE | INDEX | RULE | SEQUENCE | TABLE | TYPE | VIEW ] <objname>
|
COLUMN <relation>.<attribute> |
AGGREGATE <aggname> <aggtype> |
FUNCTION <funcname> (arg1, arg2, ...) |
OPERATOR <op> (leftoperand_typ rightoperand_typ) |
TRIGGER <triggername> ON relname>
Mike Mascari
(mascarim@yahoo.com)
Implements the CREATE CONSTRAINT TRIGGER and SET CONSTRAINTS commands.
TODO:
Generic builtin trigger procedures
Automatic execution of appropriate CREATE CONSTRAINT... at CREATE TABLE
Support of new trigger type in pg_dump
Swapping of huge # of events to disk
Jan
additional argument specifying the kind of lock to acquire/release (or
'NoLock' to do no lock processing). Ensure that all relations are locked
with some appropriate lock level before being examined --- this ensures
that relevant shared-inval messages have been processed and should prevent
problems caused by concurrent VACUUM. Fix several bugs having to do with
mismatched increment/decrement of relation ref count and mismatched
heap_open/close (which amounts to the same thing). A bogus ref count on
a relation doesn't matter much *unless* a SI Inval message happens to
arrive at the wrong time, which is probably why we got away with this
sloppiness for so long. Repair missing grab of AccessExclusiveLock in
DROP TABLE, ALTER/RENAME TABLE, etc, as noted by Hiroshi.
Recommend 'make clean all' after pulling this update; I modified the
Relation struct layout slightly.
Will post further discussion to pghackers list shortly.
