lookup info in the relcache for index access method support functions.
This makes a huge difference for dynamically loaded support functions,
and should save a few cycles even for built-in ones. Also tweak dfmgr.c
so that load_external_function is called only once, not twice, when
doing fmgr_info for a dynamically loaded function. All per performance
gripe from Teodor Sigaev, 5-Oct-01.
check *can* return HEAPTUPLE_INSERT_IN_PROGRESS or HEAPTUPLE_DELETE_IN_PROGRESS,
even though we have ShareLock on the relation. To wit, this can happen
if the tuple was inserted/deleted by our own transaction. Per report from
Justin Clift 9/23.
Assign the fixed user id 1 to the user created by initdb.
A stand-alone backend will always set the user id to 1.
(Consequently, the name of that user is no longer important.)
In stand-alone mode, the user id 1 will have implicit superuser
status, to allow repairs even if there are no users defined.
Print a warning message when starting in stand-alone mode when no
users are defined.
Disallow dropping the current user and session user.
Granting/revoking superuser status also grants/revokes usecatupd.
(Previously, it would never grant it back. This could lead to "deadlocks".)
CREATE USER and CREATE GROUP will start allocating user ids at 100
(unless explicitly specified), to prevent accidental creation of a
superuser (plus some room for future extensions).
We will no longer try to send elog messages to the client before we have
initialized backend libpq (oops); however, reporting bogus commandline
switches via elog does work now (not irrelevant, because of PGOPTIONS).
Fix problem with inappropriate sending of checkpoint-process messages
to stderr.
If there's anyone out there who's actually using datatype-defined
default values, this will be an incompatible change in behavior ...
but the old behavior was so broken that I doubt anyone was using it.
buffer manager with 'pg_clog', a specialized access method modeled
on pg_xlog. This simplifies startup (don't need to play games to
open pg_log; among other things, OverrideTransactionSystem goes away),
should improve performance a little, and opens the door to recycling
commit log space by removing no-longer-needed segments of the commit
log. Actual recycling is not there yet, but I felt I should commit
this part separately since it'd still be useful if we chose not to
do transaction ID wraparound.
pgsql-hackers. pg_opclass now has a row for each opclass supported by each
index AM, not a row for each opclass name. This allows pg_opclass to show
directly whether an AM supports an opclass, and furthermore makes it possible
to store additional information about an opclass that might be AM-dependent.
pg_opclass and pg_amop now store "lossy" and "haskeytype" information that we
previously expected the user to remember to provide in CREATE INDEX commands.
Lossiness is no longer an index-level property, but is associated with the
use of a particular operator in a particular index opclass.
Along the way, IndexSupportInitialize now uses the syscaches to retrieve
pg_amop and pg_amproc entries. I find this reduces backend launch time by
about ten percent, at the cost of a couple more special cases in catcache.c's
IndexScanOK.
Initial work by Oleg Bartunov and Teodor Sigaev, further hacking by Tom Lane.
initdb forced.
default, but OIDS are removed from many system catalogs that don't need them.
Some interesting side effects: TOAST pointers are 20 bytes not 32 now;
pg_description has a three-column key instead of one.
Bugs fixed in passing: BINARY cursors work again; pg_class.relhaspkey
has some usefulness; pg_dump dumps comments on indexes, rules, and
triggers in a valid order.
initdb forced.
Note: I didn't force an initdb, figuring that one today was enough.
However, there is a new function in pg_proc.h, and pg_dump won't be
able to dump partial indexes until you add that function.
per previous discussion on pghackers. Most of the duplicate code in
different AMs' ambuild routines has been moved out to a common routine
in index.c; this means that all index types now do the right things about
inserting recently-dead tuples, etc. (I also removed support for EXTEND
INDEX in the ambuild routines, since that's about to go away anyway, and
it cluttered the code a lot.) The retail indextuple deletion routines have
been replaced by a "bulk delete" routine in which the indexscan is inside
the access method. I haven't pushed this change as far as it should go yet,
but it should allow considerable simplification of the internal bookkeeping
for deletions. Also, add flag columns to pg_am to eliminate various
hardcoded tests on AM OIDs, and remove unused pg_am columns.
Fix rtree and gist index types to not attempt to store NULLs; before this,
gist usually crashed, while rtree managed not to crash but computed wacko
bounding boxes for NULL entries (which might have had something to do with
the performance problems we've heard about occasionally).
Add AtEOXact routines to hash, rtree, and gist, all of which have static
state that needs to be reset after an error. We discovered this need long
ago for btree, but missed the other guys.
Oh, one more thing: concurrent VACUUM is now the default.
stub) into the rest of the system. Adopt a cleaner approach to preventing
deadlock in concurrent heap_updates: allow RelationGetBufferForTuple to
select any page of the rel, and put the onus on it to lock both buffers
in a consistent order. Remove no-longer-needed isExtend hack from
API of ReleaseAndReadBuffer.
do anything yet, but it has the necessary connections to initialization
and so forth. Make some gestures towards allowing number of blocks in
a relation to be BlockNumber, ie, unsigned int, rather than signed int.
(I doubt I got all the places that are sloppy about it, yet.) On the
way, replace the hardwired NLOCKS_PER_XACT fudge factor with a GUC
variable.
rules and triggers by OID. So, even though we have no cross-references
in the system catalogs to pg_rewrite.oid or pg_trigger.oid, we'd better
have unique indexes on them. Put back pg_rewrite_oid_index, which I
mistakenly removed a few days ago, and add pg_trigger_oid_index.
pg_database now has unique indexes on oid and on datname.
pg_shadow now has unique indexes on usename and on usesysid.
pg_am now has unique index on oid.
pg_opclass now has unique index on oid.
pg_amproc now has unique index on amid+amopclaid+amprocnum.
Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID syscache.
Remove index on pg_listener and associated syscache for performance reasons
(caching rows that are certain to change before you need 'em again is
rather pointless).
Change pg_attrdef's nonunique index on adrelid into a unique index on
adrelid+adnum.
Fix various incorrect settings of pg_class.relisshared, make that the
primary reference point for whether a relation is shared or not.
IsSharedSystemRelationName() is now only consulted to initialize relisshared
during initial creation of tables and indexes. In theory we might now
support shared user relations, though it's not clear how one would get
entries for them into pg_class &etc of multiple databases.
Fix recently reported bug that pg_attribute rows created for an index all have
the same OID. (Proof that non-unique OID doesn't matter unless it's
actually used to do lookups ;-))
There's no need to treat pg_trigger, pg_attrdef, pg_relcheck as bootstrap
relations. Convert them into plain system catalogs without hardwired
entries in pg_class and friends.
Unify global.bki and template1.bki into a single init script postgres.bki,
since the alleged distinction between them was misleading and pointless.
Not to mention that it didn't work for setting up indexes on shared
system relations.
Rationalize locking of pg_shadow, pg_group, pg_attrdef (no need to use
AccessExclusiveLock where ExclusiveLock or even RowExclusiveLock will do).
Also, hold locks until transaction commit where necessary.
for GRANT/REVOKE is now just that, not "CHANGE".
On the way, migrate some of the aclitem internal representation away from
the parser and build a real parse tree instead. Also add some 'const'
qualifiers.
copy PUBLIC access rights into each newly created ACL entry. Instead
treat each ACL entry as independent flags. Also clean up some ugliness
in acl.h API.
report on old-style functions invoked by RI triggers. We had a number of
other places that were being sloppy about which memory context FmgrInfo
subsidiary data will be allocated in. Turns out none of them actually
cause a problem in 7.1, but this is for arcane reasons such as the fact
that old-style triggers aren't supported anyway. To avoid getting burnt
later, I've restructured the trigger support so that we don't keep trigger
FmgrInfo structs in relcache memory. Some other related cleanups too:
it's not really necessary to call fmgr_info at all while setting up
the index support info in relcache entries, because those ScanKeyEntry
structs are never used to invoke the functions. This should speed up
relcache initialization a tiny bit.
basically want your guys feedback. I have sprinkled some of my q's thru
the text delimited with the @@ symbol. It seems to work perfectly.
[ Removed @@ comments because patch was reviewed. ]
At the moment it does CHECK constraints only, with inheritance. However,
due to the problem mentioned before with the mismatching between inherited
constraints it may be wise to disable the inheritance feature for a while.
it is written in an extensible fashion to support future dropping of other
types of constraint, and is well documented.
Please send me your comments, check my use of locking, updating of
indices, use of ERROR and NOTICE, etc. and I will rework the patch based
on feedback until everyone
is happy with it...
Christopher Kings
create_index_paths are not immediately discarded, but are available for
subsequent planner work. This allows avoiding redundant syscache lookups
in several places. Change interface to operator selectivity estimation
procedures to allow faster and more flexible estimation.
Initdb forced due to change of pg_proc entries for selectivity functions!
constraint names.
> > A reasonable interpretation of DROP CONSTRAINT "foo" is to drop *all*
> > constraints named "foo" on the target table.
>
> Then it should probably be a good thing to avoid the automatic
> generation of
> duplicate names? I might take a look at that, actually...
>
Christopher Kings-Lynne
a separate statement (though it can still be invoked as part of VACUUM, too).
pg_statistic redesigned to be more flexible about what statistics are
stored. ANALYZE now collects a list of several of the most common values,
not just one, plus a histogram (not just the min and max values). Random
sampling is used to make the process reasonably fast even on very large
tables. The number of values and histogram bins collected is now
user-settable via an ALTER TABLE command.
There is more still to do; the new stats are not being used everywhere
they could be in the planner. But the remaining changes for this project
should be localized, and the behavior is already better than before.
A not-very-related change is that sorting now makes use of btree comparison
routines if it can find one, rather than invoking '<' twice.
clause with an alias is a <subquery> and therefore hides table references
appearing within it, according to the spec. This is the same as the
preliminary patch I posted to pgsql-patches yesterday, plus some really
grotty code in ruleutils.c to reverse-list a query tree with the correct
alias name depending on context. I'd rather not have done that, but unless
we want to force another initdb for 7.1, there's no other way for now.
two transactions create the same table name concurrently, the one that
fails will complain about unique index pg_class_relname_index, rather than
about pg_type_typname_index which'll confuse most people. Free side
benefit: pg_class.reltype is correctly linked to the pg_type entry now.
It's been zero in all but the preloaded pg_class entries since who knows
when.
allocated by plan nodes are not leaked at end of query. This doesn't
really matter for normal queries, but it sure does for queries invoked
repetitively inside SQL functions. Clean up some other grotty code
associated with tupdescs, and fix a few other memory leaks exposed by
tests with simple SQL functions.
than forcing 'plain'. This probably does not matter right now, but I
think it needs to be consistent with the regular (not-functional) index
case, where attstorage is copied from the underlying table. Clean up
some other dead and infelicitous code too.
bothering to check the return value --- which meant that in case the
update or delete failed because of a concurrent update, you'd not find
out about it, except by observing later that the transaction produced
the wrong outcome. There are now subroutines simple_heap_update and
simple_heap_delete that should be used anyplace that you're not prepared
to do the full nine yards of coping with concurrent updates. In
practice, that seems to mean absolutely everywhere but the executor,
because *noplace* else was checking.
1. Distinguish cases where a Datum representing a tuple datatype is an OID
from cases where it is a pointer to TupleTableSlot, and make sure we use
the right typlen in each case.
2. Make fetchatt() and related code support 8-byte by-value datatypes on
machines where Datum is 8 bytes. Centralize knowledge of the available
by-value datatype sizes in two macros in tupmacs.h, so that this will be
easier if we ever have to do it again.
table that inherits from a temp table. Make sure the right things happen
if one creates a temp table, creates another temp that inherits from it,
then renames the first one. (Previously, system would end up trying to
delete the temp tables in the wrong order.)
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.
message about recursive use of a syscache. Also remove most of the
specialized indexscan routines in indexing.c --- it turns out that
catcache.c is perfectly able to perform the indexscan for itself,
in fact has already looked up all the information needed to do so!
This should be faster as well as needing far less boilerplate code.
(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.
kibitzing from Tom Lane. Large objects are now all stored in a single
system relation "pg_largeobject" --- no more xinv or xinx files, no more
relkind 'l'. This should offer substantial performance improvement for
large numbers of LOs, since there won't be directory bloat anymore.
It'll also fix problems like running out of locktable space when you
access thousands of LOs in one transaction.
Also clean up cruft in read/write routines. LOs with "holes" in them
(never-written byte ranges) now work just like Unix files with holes do:
a hole reads as zeroes but doesn't occupy storage space.
INITDB forced!
as well allow DROP multiple INDEX, RULE, TYPE as well. Add missing
CommandCounterIncrement to DROP loop, which could cause trouble otherwise
with multiple DROP of items affecting same catalog entries. Try to
bring a little consistency to various error messages using 'does not exist',
'nonexistent', etc --- I standardized on 'does not exist' since that's
what the vast majority of the existing uses seem to be.
> Regression tests opr_sanity and sanity_check are now failing.
Um, Bruce, I've said several times that I didn't think Perchine's large
object changes should be applied until someone had actually reviewed
them.
I tested it restoring my database with > 100000 BLOBS, and dumping it out.
But unfortunatly I can not restore it back due to problems in pg_dump.
--
Sincerely Yours,
Denis Perchine
source directory. This involves mostly makefiles using $(srcdir) when they
might have used ".". (Regression tests don't work with this, yet.)
Sort out usage of CPPFLAGS, CFLAGS (and CXXFLAGS). Add "override" keyword
in most places, to preserve necessary flags even when the user overrode the
flags.
> this is patch v 0.4 to support transactions with BLOBs.
> All BLOBs are in one table. You need to make initdb.
>
> --
> Sincerely Yours,
> Denis Perchine
took some rejiggering of typename and ACL parsing, as well as moving
parse_analyze call out of parser(). Restructure postgres.c processing
so that parse analysis and rewrite are skipped when in abort-transaction
state. Only COMMIT and ABORT statements will be processed beyond the raw
parser() phase. This addresses problem of parser failing with database access
errors while in aborted state (see pghackers discussions around 7/28/00).
Also fix some bugs with COMMIT/ABORT statements appearing in the middle of
a single query input string.
Function, operator, and aggregate arguments/results can now use full
TypeName production, in particular foo[] for array types.
DROP OPERATOR and COMMENT ON OPERATOR were broken for unary operators.
Allow CREATE AGGREGATE to accept unquoted numeric constants for initcond.
would close and then re-open rel being truncated. Depending on the
luck of the draw, the re-opened relcache entry might or might not be
at the same physical location as before. Unfortunately, if it wasn't
then heap_truncate would crash and burn, because it still had a pointer
at the old location. Fix is to open and then close rel in
RelationTruncateIndexes, so that rel's refcount never goes to zero
until heap_truncate is done.
(Don't forget that an alias is required.) Views reimplemented as expanding
to subselect-in-FROM. Grouping, aggregates, DISTINCT in views actually
work now (he says optimistically). No UNION support in subselects/views
yet, but I have some ideas about that. Rule-related permissions checking
moved out of rewriter and into executor.
INITDB REQUIRED!
DESTDIR=/else/where' and prepends the value of DESTDIR to the full
installation paths (e.g., /else/where/usr/local/pgsql/bin). This allows
users to install the package into a location different from the one that
was configured and hard-coded into various scripts, e.g., for creating
binary packages.
DESTDIR is in many cases preferrable over `make install
prefix=/else/where' because
a) `prefix' affects the path that is hard-coded into the files, which can
lead to a `make install prefix=xxx' (as done by the regression test
driver) corrupting the files in the source tree with wrong paths.
b) it doesn't work at all if a directory was overridden to not depend on
`prefix', e.g., --sysconfdir=/etc.
(Updating the regression test driver to use DESTDIR is a separate
undertaking.)
See also autoconf@gnu.org, From: Akim Demaille <akim@epita.fr>, Date: 08
Sep 2000 12:48:59 +0200, Message-ID:
<mv4em2vb1lw.fsf@nostromo.lrde.epita.fr>, Subject: Re: HTML format
documentation.
for views. Views are now have a "relkind" of
RELKIND_VIEW instead of RELKIND_RELATION.
Also, views no longer have actual heap storage
files.
The following changes were made
1. CREATE VIEW sets the new relkind
2. The executor complains if a DELETE or
INSERT references a view.
3. DROP RULE complains if an attempt is made
to delete a view SELECT rule.
4. CREATE RULE "_RETmytable" AS ON SELECT TO mytable DO INSTEAD ...
1. checks to make sure mytable is empty.
2. sets the relkind to RELKIND_VIEW.
3. deletes the heap storage files.
5. LOCK myview is not allowed. :)
6. the regression test type_sanity was changed to
account for the new relkind value.
7. CREATE INDEX ON myview ... is not allowed.
8. VACUUM myview is not allowed.
VACUUM automatically skips views when do the entire
database.
9. TRUNCATE myview is not allowed.
THINGS LEFT TO THINK ABOUT
o pg_views
o pg_dump
o pgsql (\d \dv)
o Do we really want to be able to inherit from views?
o Is 'DROP TABLE myview' OK?
--
Mark Hollomon
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.
pg_proc.c (where it's actually used). Fix it to correctly handle tlists
that contain resjunk target items, and improve error messages. This
addresses bug reported by Krupnikov 6-July-00.
macros where appropriate (the code used to have several different ways
of doing that, including Int32, Int8, UInt8, ...). Remove last few
references to float32 and float64 typedefs --- it's all float4/float8
now. The typedefs themselves should probably stay in c.h for a release
or two, though, to avoid breaking user-written C functions.
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 :-(.
There's now only one transition value and transition function.
NULL handling in aggregates is a lot cleaner. Also, use Numeric
accumulators instead of integer accumulators for sum/avg on integer
datatypes --- this avoids overflow at the cost of being a little slower.
Implement VARIANCE() and STDDEV() aggregates in the standard backend.
Also, enable new LIKE selectivity estimators by default. Unrelated
change, but as long as I had to force initdb anyway...
pass-by-ref data types --- eg, an index on lower(textfield) --- no longer
leak memory during index creation or update. Clean up a lot of redundant
code ... did you know that copy, vacuum, truncate, reindex, extend index,
and bootstrap each basically duplicated the main executor's logic for
extracting information about an index and preparing index entries?
Functional indexes should be a little faster now too, due to removal
of repeated function lookups.
CREATE INDEX 'opt_type' clause is deimplemented by these changes,
but I haven't removed it from the parser yet (need to merge with
Thomas' latest change set first).
Tom Lane
Peter Eisentraut
Hiroshi Inoue
Jan Wieck
Bruce Momjian
Vadim B. Mikheev