Previously reported as ERRCODE_ADMIN_SHUTDOWN, this case is now
reported as ERRCODE_T_R_DATABASE_DROPPED. No message text change.
Unlikely to happen on most servers, so low impact change to allow
session poolers to correctly handle this situation.
Tatsuo Ishii, edits by me, review by Robert Haas
With this patch, pg_basebackup doesn't write a backup_label file in the
data directory, so it doesn't interfere with a pg_start/stop_backup() based
backup anymore. backup_label is still included in the backup, but it is
injected directly into the tar stream.
Heikki Linnakangas, reviewed by Fujii Masao and Magnus Hagander.
This can be used to build 64 bit Windows binaries, not only on 64 bit
Windows but on supported cross-compiling hosts including 32 bit Windows,
Cygwin, Darwin and Linux.
When included, this makes the base backup a complete working
"clone" of the initial database, ready to have a postmaster
started against it without the need to set up any log archiving
or similar.
Magnus Hagander, reviewed by Fujii Masao and Heikki Linnakangas
Synchronize pg_config.h.in with configure.in (someone must have
forgotten to run autoheader or autoreconf), and clean up some spurious
change in configure introduced by the last commit there.
There isn't any need to track this state on a table-wide basis, and trying
to do so introduces undesirable semantic fuzziness. Move the flag to
pg_index, where it clearly describes just a single index and can be
immutable after index creation.
This feature allows a unique or pkey constraint to be created using an
already-existing unique index. While the constraint isn't very
functionally different from the bare index, it's nice to be able to do that
for documentation purposes. The main advantage over just issuing a plain
ALTER TABLE ADD UNIQUE/PRIMARY KEY is that the index can be created with
CREATE INDEX CONCURRENTLY, so that there is not a long interval where the
table is locked against updates.
On the way, refactor some of the code in DefineIndex() and index_create()
so that we don't have to pass through those functions in order to create
the index constraint's catalog entries. Also, in parse_utilcmd.c, pass
around the ParseState pointer in struct CreateStmtContext to save on
notation, and add error location pointers to some error reports that didn't
have one before.
Gurjeet Singh, reviewed by Steve Singer and Tom Lane
While doing this, also move base backup options into
a struct instead of increasing the number of parameters
to multiple functions for each new option.
This tool makes it possible to do the pg_start_backup/
copy files/pg_stop_backup step in a single command.
There are still some steps to be done before this is a
complete backup solution, such as the ability to stream
the required WAL logs, but it's still usable, and
could do with some buildfarm coverage.
In passing, make the checkpoint request optionally
fast instead of hardcoding it.
Magnus Hagander, reviewed by Fujii Masao and Dimitri Fontaine
As in commit fb4c5d2798 on 2011-01-21,
this avoids spurious debug messages and allows idempotent changes at
any time. Along the way, make assign_XactIsoLevel allow idempotent
changes even when not within a subtransaction, to be consistent with
the new coding of assign_transaction_read_only and because there's
no compelling reason to do otherwise.
Kevin Grittner, with some adjustments.
The new coding avoids a spurious debug message when a transaction
that has changed the isolation level has been rolled back. It also
allows the property to be freely changed to the current value within
a subtransaction.
Kevin Grittner, with one small change by me.
Failure to do so can lead to constraint violations. This was broken by
commit 1ddc2703a9 on 2010-02-07, so
back-patch to 9.0.
Noah Misch. Regression test by me.
backend, as far as the postmaster shutdown logic is concerned. That means,
fast shutdown will wait for WAL sender processes to exit before signaling
bgwriter to finish. This avoids race conditions between a base backup stopping
or starting, and bgwriter writing the shutdown checkpoint WAL record. We don't
want e.g the end-of-backup WAL record to be written after the shutdown
checkpoint.
Makes it easier to parse mainly the BASE_BACKUP command
with it's options, and avoids having to manually deal
with quoted identifiers in the label (previously broken),
and makes it easier to add new commands and options in
the future.
In passing, refactor the case statement in the walsender
to put each command in it's own function.
When the exit waits until the whole backup completes, it may take
a very long time.
In passing, add back an error check in the main loop so we detect
clients that disconnect much earlier if the backup is large.
Fix broken test for pre-existing postmaster, caused by wrong code for
appending lines to the lockfile; don't write a failed listen_address
setting into the lockfile; don't arbitrarily change the location of the
data directory in the lockfile compared to previous releases; provide more
consistent and useful definitions of the socket path and listen_address
entries; avoid assuming that pg_ctl has the same DEFAULT_PGSOCKET_DIR as
the postmaster; assorted code style improvements.
In an inherited UPDATE/DELETE, each target table has its own subplan,
because it might have a column set different from other targets. This
means that the resjunk columns we add to support EvalPlanQual might be
at different physical column numbers in each subplan. The EvalPlanQual
rewrite I did for 9.0 failed to account for this, resulting in possible
misbehavior or even crashes during concurrent updates to the same row,
as seen in a recent report from Gordon Shannon. Revise the data structure
so that we track resjunk column numbers separately for each subplan.
I also chose to move responsibility for identifying the physical column
numbers back to executor startup, instead of assuming that numbers derived
during preprocess_targetlist would stay valid throughout subsequent
massaging of the plan. That's a bit slower, so we might want to consider
undoing it someday; but it would complicate the patch considerably and
didn't seem justifiable in a bug fix that has to be back-patched to 9.0.
Add BASE_BACKUP command to walsender, allowing it to stream a
base backup to the client (in tar format). The syntax is still
far from ideal, that will be fixed in the switch to use a proper
grammar for walsender.
No client included yet, will come as a separate commit.
Magnus Hagander and Heikki Linnakangas
Move the actual functionality into a separate function that's
easier to call internally, and change the SQL-callable function
to be a wrapper calling this.
Also create a pg_abort_backup() function, only callable internally,
that does only the most vital parts of pg_stop_backup(), making it
safe(r) to call from error handlers.
Add support for reading back information about the symbolic
links we've created with pgsymlink(), which are actually
Junction Points. Just like pgsymlink() can only create directory
symlinks, pgreadlink() can only read directory symlinks.
This will support fixing contrib/intarray (and probably other places)
so that they don't have to fail on arrays that contain a null bitmap
but no live null entries.
The only use we have had for amindexnulls is in determining whether an
index is safe to cluster on; but since the addition of the amclusterable
flag, that usage is pretty redundant.
In passing, clean up assorted sloppiness from the last patch that touched
pg_am.h: Natts_pg_am was wrong, and ambuildempty was not documented.
The original coding could combine duplicate entries only when they
originated from the same qual condition. In particular it could not
combine cases where multiple qual conditions all give rise to full-index
scan requests, which is an expensive case well worth optimizing. Refactor
so that duplicates are recognized across all the quals.
Add more "internal" arguments so that these pg_proc entries reflect the
current preferred API. This is purely a cosmetic change, since GIN doesn't
actually consult the pg_proc entry when calling a support function.
Accordingly, no catversion bump.
Per my recent proposal(s). Null key datums can now be returned by
extractValue and extractQuery functions, and will be stored in the index.
Also, placeholder entries are made for indexable items that are NULL or
contain no keys according to extractValue. This means that the index is
now always complete, having at least one entry for every indexed heap TID,
and so we can get rid of the prohibition on full-index scans. A full-index
scan is implemented much the same way as partial-match scans were already:
we build a bitmap representing all the TIDs found in the index, and then
drive the results off that.
Also, introduce a concept of a "search mode" that can be requested by
extractQuery when the operator requires matching to empty items (this is
just as cheap as matching to a single key) or requires a full index scan
(which is not so cheap, but it sure beats failing or giving wrong answers).
The behavior remains backward compatible for opclasses that don't return
any null keys or request a non-default search mode.
Using these features, we can now make the GIN index opclass for anyarray
behave in a way that matches the actual anyarray operators for &&, <@, @>,
and = ... which it failed to do before in assorted corner cases.
This commit fixes the core GIN code and ginarrayprocs.c, updates the
documentation, and adds some simple regression test cases for the new
behaviors using the array operators. The tsearch and contrib GIN opclass
support functions still need to be looked over and probably fixed.
Another thing I intend to fix separately is that this is pretty inefficient
for cases where more than one scan condition needs a full-index search:
we'll run duplicate GinScanEntrys, each one of which builds a large bitmap.
There is some existing logic to merge duplicate GinScanEntrys but it needs
refactoring to make it work for entries belonging to different scan keys.
Note that most of gin.h has been split out into a new file gin_private.h,
so that gin.h doesn't export anything that's not supposed to be used by GIN
opclasses or the rest of the backend. I did quite a bit of other code
beautification work as well, mostly fixing comments and choosing more
appropriate names for things.
This can be overriden by using NOREPLICATION on the CREATE ROLE
statement, but by default they will have it, making it backwards
compatible and "less surprising" (given that superusers normally
override all checks).
Add new function pg_sequence_parameters that returns a sequence's start,
minimum, maximum, increment, and cycle values, and use that in the view.
(bug #5662; design suggestion by Tom Lane)
Also slightly adjust the view's column order and permissions after review of
SQL standard.
Foreign tables are a core component of SQL/MED. This commit does
not provide a working SQL/MED infrastructure, because foreign tables
cannot yet be queried. Support for foreign table scans will need to
be added in a future patch. However, this patch creates the necessary
system catalog structure, syntax support, and support for ancillary
operations such as COMMENT and SECURITY LABEL.
Shigeru Hanada, heavily revised by Robert Haas
This is advantageous first because it allows us to hash the smaller table
regardless of the outer-join type, and second because hash join can be more
flexible than merge join in dealing with arbitrary join quals in a FULL
join. For merge join all the join quals have to be mergejoinable, but hash
join will work so long as there's at least one hashjoinable qual --- the
others can be any condition. (This is true essentially because we don't
keep per-inner-tuple match flags in merge join, while hash join can do so.)
To do this, we need a has-it-been-matched flag for each tuple in the
hashtable, not just one for the current outer tuple. The key idea that
makes this practical is that we can store the match flag in the tuple's
infomask, since there are lots of bits there that are of no interest for a
MinimalTuple. So we aren't increasing the size of the hashtable at all for
the feature.
To write this without turning the hash code into even more of a pile of
spaghetti than it already was, I rewrote ExecHashJoin in a state-machine
style, similar to ExecMergeJoin. Other than that decision, it was pretty
straightforward.
Instead, declare a public wrapper of the sole function using it for
external callers, so that they don't have to always pass a NULL
argument.
Author: Kevin Grittner
The contents of an unlogged table are WAL-logged; thus, they are not
available on standby servers and are truncated whenever the database
system enters recovery. Indexes on unlogged tables are also unlogged.
Unlogged GiST indexes are not currently supported.
This privilege is required to do Streaming Replication, instead of
superuser, making it possible to set up a SR slave that doesn't
have write permissions on the master.
Superuser privileges do NOT override this check, so in order to
use the default superuser account for replication it must be
explicitly granted the REPLICATION permissions. This is backwards
incompatible change, in the interest of higher default security.
The "date" type supports a wider range of dates than int64 timestamps do.
However, there is pre-int64-timestamp code in the planner that assumes that
all date values can be converted to timestamp with impunity. Fortunately,
what we really need out of the conversion is always a double (float8)
value; so even when the date is out of timestamp's range it's possible to
produce a sane answer. All we need is a code path that doesn't try to
force the result into int64. Per trouble report from David Rericha.
Back-patch to all supported versions. Although this is surely a corner
case, there's not much point in advertising a date range wider than
timestamp's if we will choke on such values in unexpected places.
This is to avoid use of the C++ keywords "bitand" and "bitor" in
the header file utils/varbit.h. Note the functions' SQL-level
names are not changed, only their C-level names.
In passing, make some comments in varbit.c conform to project-standard
layout.
"private" is a keyword in C++, so this breaks the poorly-enforced policy
that header files should be include-able in C++ code. Per report from
Craig Ringer and some investigation with cpluspluscheck.
My previous commit, 85cff3ce7f on
2010-12-25, failed to update errcodes.sgml or plerrcodes.h. This patch
corrects that oversight, per a gripe from Tom Lane, and also corrects
a typographical error.
cleanup stage to finish incomplete inserts or splits anymore. There was two
reasons for the cleanup step:
1. When a new tuple was inserted to a leaf page, the downlink in the parent
needed to be updated to contain (ie. to be consistent with) the new key.
Updating the parent in turn might require recursively updating the parent of
the parent. We now handle that by updating the parent while traversing down
the tree, so that when we insert the leaf tuple, all the parents are already
consistent with the new key, and the tree is consistent at every step.
2. When a page is split, we need to insert the downlink for the new right
page(s), and update the downlink for the original page to not include keys
that moved to the right page(s). We now handle that by setting a new flag,
F_FOLLOW_RIGHT, on the non-rightmost pages in the split. When that flag is
set, scans always follow the rightlink, regardless of the NSN mechanism used
to detect concurrent page splits. That way the tree is consistent right after
split, even though the downlink is still missing. This is very similar to the
way B-tree splits are handled. When the downlink is inserted in the parent,
the flag is cleared. To keep the insertion algorithm simple, when an
insertion sees an incomplete split, indicated by the F_FOLLOW_RIGHT flag, it
finishes the split before doing anything else.
These changes allow removing the whole "invalid tuple" mechanism, but I
retained the scan code to still follow invalid tuples correctly. While we
don't create any such tuples anymore, we want to handle them gracefully in
case you pg_upgrade a GiST index that has them. If we encounter any on an
insert, though, we just throw an error saying that you need to REINDEX.
The issue that got me into doing this is that if you did a checkpoint while
an insert or split was in progress, and the checkpoint finishes quickly so
that there is no WAL record related to the insert between RedoRecPtr and the
checkpoint record, recovery from that checkpoint would not know to finish
the incomplete insert. IOW, we have the same issue we solved with the
rm_safe_restartpoint mechanism during normal operation too. It's highly
unlikely to happen in practice, and this fix is far too large to backpatch,
so we're just going to live with in previous versions, but this refactoring
fixes it going forward.
With this patch, you don't get the annoying
'index "FOO" needs VACUUM or REINDEX to finish crash recovery' notices
anymore if you crash at an unfortunate moment.
Add support for collecting "minidump" style crash dumps on
Windows, by setting up an exception handling filter. Crash
dumps will be generated in PGDATA/crashdumps if the directory
is created (the existance of the directory is used as on/off
switch for the generation of the dumps).
Craig Ringer and Magnus Hagander
We don't actually need optreset, because we can easily fix the code to
ensure that it's cleanly restartable after having completed a scan over the
argv array; which is the only case we need to restart in. Getting rid of
it avoids a class of interactions with the system libraries and allows
reversion of my change of yesterday in postmaster.c and postgres.c.
Back-patch to 8.4. Before that the getopt code was a bit different anyway.
This commit replaces pg_class.relistemp with pg_class.relpersistence;
and also modifies the RangeVar node type to carry relpersistence rather
than istemp. It also removes removes rd_istemp from RelationData and
instead performs the correct computation based on relpersistence.
For clarity, we add three new macros: RelationNeedsWAL(),
RelationUsesLocalBuffers(), and RelationUsesTempNamespace(), so that we
can clarify the purpose of each check that previous depended on
rd_istemp.
This is intended as infrastructure for the upcoming unlogged tables
patch, as well as for future possible work on global temporary tables.
mkdir_p and check_data_dir will be useful in CREATE TABLESPACE, since we
have agreed that that command should handle subdirectory creation just like
initdb creates the PGDATA directory. Push them into src/port/ so that they
are available to both initdb and the backend. Rename to pg_mkdir_p and
pg_check_dir, just to be on the safe side. Add FreeBSD's copyright notice
to pgmkdirp.c, since that's where the code came from originally (this
really should have been in initdb.c). Very marginal code/comment cleanup.
Recent versions of the Linux system header files cause xlogdefs.h to
believe that open_datasync should be the default sync method, whereas
formerly fdatasync was the default on Linux. open_datasync is a bad
choice, first because it doesn't actually outperform fdatasync (in fact
the reverse), and second because we try to use O_DIRECT with it, causing
failures on certain filesystems (e.g., ext4 with data=journal option).
This part of the patch is largely per a proposal from Marti Raudsepp.
More extensive changes are likely to follow in HEAD, but this is as much
change as we want to back-patch.
Also clean up confusing code and incorrect documentation surrounding the
fsync_writethrough option. Those changes shouldn't result in any actual
behavioral change, but I chose to back-patch them anyway to keep the
branches looking similar in this area.
In 9.0 and HEAD, also do some copy-editing on the WAL Reliability
documentation section.
Back-patch to all supported branches, since any of them might get used
on modern Linux versions.
First, avoid scanning the whole ProcArray once we know there
are at least commit_siblings active; second, skip the check
altogether if commit_siblings = 0.
Greg Smith
an old transaction running in the master, and a lot of transactions have
started and finished since, and a WAL-record is written in the gap between
the creating the running-xacts snapshot and WAL-logging it, recovery will fail
with "too many KnownAssignedXids" error. This bug was reported by
Joachim Wieland on Nov 19th.
In the same scenario, when fewer transactions have started so that all the
xids fit in KnownAssignedXids despite the first bug, a more serious bug
arises. We incorrectly initialize the clog code with the oldest still running
transaction, and when we see the WAL record belonging to a transaction with
an XID larger than one that committed already before the checkpoint we're
recovering from, we zero the clog page containing the already committed
transaction, leading to data loss.
In hindsight, trying to track xids in the known-assigned-xids array before
seeing the running-xacts record was too complicated. To fix that, hold
XidGenLock while the running-xacts snapshot is taken and WAL-logged. That
ensures that no transaction can begin or end in that gap, so that in recvoery
we know that the snapshot contains all transactions running at that point in
WAL.
This commit represents a rather heavily editorialized version of
Teodor's builtin_knngist_itself-0.8.2 and builtin_knngist_proc-0.8.1
patches. I redid the opclass API to add a separate Distance method
instead of turning the Consistent method into an illogical mess,
fixed some bit-rot in the rbtree interfaces, and generally worked over
the code style and comments.
There's still no non-code documentation to speak of, but I'll work on
that separately. Some contrib-module changes are also yet to come
(right now, point <-> point is the only KNN-ified operator).
Teodor Sigaev and Tom Lane
This eliminates some crufty, special-purpose code and, as a non-trivial
side benefit, allows recovery.conf parameters to be unquoted.
Dimitri Fontaine, with review and cleanup by Alvaro Herrera, Itagaki
Takahiro, and me.
This is a heavily revised version of builtin_knngist_core-0.9. The
ordering operators are no longer mixed in with actual quals, which would
have confused not only humans but significant parts of the planner.
Instead, ordering operators are carried separately throughout planning and
execution.
Since the API for ambeginscan and amrescan functions had to be changed
anyway, this commit takes the opportunity to rationalize that a bit.
RelationGetIndexScan no longer forces a premature index_rescan call;
instead, callers of index_beginscan must call index_rescan too. Aside from
making the AM-side initialization logic a bit less peculiar, this has the
advantage that we do not make a useless extra am_rescan call when there are
runtime key values. AMs formerly could not assume that the key values
passed to amrescan were actually valid; now they can.
Teodor Sigaev and Tom Lane
Formerly we looked up the operators associated with each index (caching
them in relcache) and then the planner looked up the btree opfamily
containing such operators in order to build the btree-centric pathkey
representation that describes the index's sort order. This is quite
pointless for btree indexes: we might as well just use the index's opfamily
information directly. That saves syscache lookup cycles during planning,
and furthermore allows us to eliminate the relcache's caching of operators
altogether, which may help in reducing backend startup time.
I added code to plancat.c to perform the same type of double lookup
on-the-fly if it's ever faced with a non-btree amcanorder index AM.
If such a thing actually becomes interesting for production, we should
replace that logic with some more-direct method for identifying the
corresponding btree opfamily; but it's not worth spending effort on now.
There is considerably more to do pursuant to my recent proposal to get rid
of sort-operator-based representations of sort orderings, but this patch
grabs some of the low-hanging fruit. I'll look at the remainder of that
work after the current commitfest.
removing an infrequently occurring race condition in Hot Standby.
An xid must be assigned before a lock appears in shared memory,
rather than immediately after, else GetRunningTransactionLocks()
may see InvalidTransactionId, causing assertion failures during
lock processing on standby.
Bug report and diagnosis by Fujii Masao, fix by me.
This adds support for changing the schema of a conversion, operator,
operator class, operator family, text search configuration, text search
dictionary, text search parser, or text search template.
Dimitri Fontaine, with assorted corrections and other kibitzing.
After a SQL object is created, we provide an opportunity for security
or logging plugins to get control; for example, a security label provider
could use this to assign an initial security label to newly created
objects. The basic infrastructure is (hopefully) reusable for other types
of events that might require similar treatment.
KaiGai Kohei, with minor adjustments.
supplied, also print the IP address. This allows IPv4 and IPv6 failures
to be distinguished. Also useful when a hostname resolves to multiple
IP addresses.
Also, remove use of inet_ntoa() and use our own inet_net_ntop() in all
places, including in libpq, because it is thread-safe.
This commit adds columns amoppurpose and amopsortfamily to pg_amop, and
column amcanorderbyop to pg_am. For the moment all the entries in
amcanorderbyop are "false", since the underlying support isn't there yet.
Also, extend the CREATE OPERATOR CLASS/ALTER OPERATOR FAMILY commands with
[ FOR SEARCH | FOR ORDER BY sort_operator_family ] clauses to allow the new
columns of pg_amop to be populated, and create pg_dump support for dumping
that information.
I also added some documentation, although it's perhaps a bit premature
given that the feature doesn't do anything useful yet.
Teodor Sigaev, Robert Haas, Tom Lane
Any flavor of ALTER <whatever> .. SET SCHEMA fails if (1) the object
is already in the new schema, (2) either the old or new schema is
a temp schema, or (3) either the old or new schema is the TOAST schema.
Extraced from a patch by Dimitri Fontaine, with additional hacking by me.
Currently, three conversion format specifiers are supported: %s for a
string, %L for an SQL literal, and %I for an SQL identifier. The latter
two are deliberately designed not to overlap with what sprintf() already
supports, in case we want to add more of sprintf()'s functionality here
later.
Patch by Pavel Stehule, heavily revised by me. Reviewed by Jeff Janes
and, in earlier versions, by Itagaki Takahiro and Tom Lane.
We no longer need the terminating zero entry in opfamily[], so get rid of
it. Also replace assorted ad-hoc looping logic with simple for and foreach
constructs. This code is now noticeably more readable than it was an hour
ago; credit to Robert for seeing that it could be simplified.
This eliminates the need for inefficient implementions of this
functionality in both contrib/dblink and contrib/tablefunc, so remove
them. The upcoming patch implementing an in-core format() function
will also require this functionality.
In passing, add some regression tests.
A hand-coded implementation turns out to be much faster than calling
printf(). In passing, add a few more regresion tests.
Andres Freund, with assorted, mostly cosmetic changes.
As per the ancient comment for set_rel_width, it really wasn't much good
for relations that aren't plain tables: it would never find any stats and
would always fall back on datatype-based estimates, which are often pretty
silly. Fix that by copying up width estimates from the subquery planning
process.
At some point we might want to do this for CTEs too, but that would be a
significantly more invasive patch because the sub-PlannerInfo is no longer
accessible by the time it's needed. I refrained from doing anything about
that, partly for fear of breaking the unmerged CTE-related patches.
In passing, also generate less bogus width estimates for whole-row Vars.
Per a gripe from Jon Nelson.
Fix things so that top-N sorting can be used in child Sort nodes of a
MergeAppend node, when there is a LIMIT and no intervening joins or
grouping. Actually doing this on the executor side isn't too bad,
but it's a bit messier to get the planner to cost it properly.
Per gripe from Robert Haas.
In passing, fix an oversight in the original top-N-sorting patch:
query_planner should not assume that a LIMIT can be used to make an
explicit sort cheaper when there will be grouping or aggregation in
between. Possibly this should be back-patched, but I'm not sure the
mistake is serious enough to be a real problem in practice.
In the previous coding, we simply issued ALTER SEQUENCE RESTART commands,
which do not roll back on error. This meant that an error between
truncating and committing left the sequences out of sync with the table
contents, with potentially bad consequences as were noted in a Warning on
the TRUNCATE man page.
To fix, create a new storage file (relfilenode) for a sequence that is to
be reset due to RESTART IDENTITY. If the transaction aborts, we'll
automatically revert to the old storage file. This acts just like a
rewriting ALTER TABLE operation. A penalty is that we have to take
exclusive lock on the sequence, but since we've already got exclusive lock
on its owning table, that seems unlikely to be much of a problem.
The interaction of this with usual nontransactional behaviors of sequence
operations is a bit weird, but it's hard to see what would be completely
consistent. Our choice is to discard cached-but-unissued sequence values
both when the RESTART is executed, and at rollback if any; but to not touch
the currval() state either time.
In passing, move the sequence reset operations to happen before not after
any AFTER TRUNCATE triggers are fired. The previous ordering was not
logically sensible, but was forced by the need to minimize inconsistency
if the triggers caused an error. Transactional rollback is a much better
solution to that.
Patch by Steve Singer, rather heavily adjusted by me.
temporary indexes are not WAL-logged. We used a constant LSN for temporary
indexes, on the assumption that we don't need to worry about concurrent page
splits in temporary indexes because they're only visible to the current
session. But that assumption is wrong, it's possible to insert rows and
split pages in the same session, while a scan is in progress. For example,
by opening a cursor and fetching some rows, and INSERTing new rows before
fetching some more.
Fix by generating fake increasing LSNs, used in place of real LSNs in
temporary GiST indexes.
This new field counts the number of times that a backend which writes a
buffer out to the OS must also fsync() it. This happens when the
bgwriter fsync request queue is full, and is generally detrimental to
performance, so it's good to know when it's happening. Along the way,
log a new message at level DEBUG1 whenever we fail to hand off an fsync,
so that the problem can also be seen in examination of log files
(if the logging level is cranked up high enough).
Greg Smith, with minor tweaks by me.
Having this in src/include/port.h makes no sense, now that copydir.c lives
in src/backend/strorage rather than src/port. Along the way, remove an
obsolete comment from contrib/pg_upgrade that makes reference to the old
location.
Formerly, we could convert a UNION ALL structure inside a subquery-in-FROM
into an appendrel, as a side effect of pulling up the subquery into its
parent; but top-level UNION ALL always caused use of plan_set_operations().
That didn't matter too much because you got an Append-based plan either
way. However, now that the appendrel code can do things with MergeAppend,
it's worthwhile to hack up the top-level case so it also uses appendrels.
This is a bit of a stopgap; but going much further than this will require
a major rewrite of the planner's set-operations support, which I'm not
prepared to undertake now. For the moment let's grab the low-hanging fruit.
Per my recent proposal, get rid of all the direct inspection of indexes
and manual generation of paths in planagg.c. Instead, set up
EquivalenceClasses for the aggregate argument expressions, and let the
regular path generation logic deal with creating paths that can satisfy
those sort orders. This makes planagg.c a bit more visible to the rest
of the planner than it was originally, but the approach is basically a lot
cleaner than before. A major advantage of doing it this way is that we get
MIN/MAX optimization on inheritance trees (using MergeAppend of indexscans)
practically for free, whereas in the old way we'd have had to add a whole
lot more duplicative logic.
One small disadvantage of this approach is that MIN/MAX aggregates can no
longer exploit partial indexes having an "x IS NOT NULL" predicate, unless
that restriction or something that implies it is specified in the query.
The previous implementation was able to use the added "x IS NOT NULL"
condition as an extra predicate proof condition, but in this version we
rely entirely on indexes that are considered usable by the main planning
process. That seems a fair tradeoff for the simplicity and functionality
gained.
and related routines.
We already had a redundant FunctionCallInfoData struct in FuncExprState,
but were using that copy only in set-returning-function cases, to avoid
keeping function evaluation state in the expression tree for the benefit
of plpgsql's "simple expression" logic. But of course that didn't work
anyway. Given the recent fixes in plpgsql there is no need to have two
separate behaviors here. Getting rid of the local FunctionCallInfoData
structs should make things a little faster (because we don't need to do
InitFunctionCallInfoData each time), and it also makes for a noticeable
reduction in stack space consumption during recursive calls.
The core of this patch is hash_array() and associated typcache
infrastructure, which works just about exactly like the existing support
for array comparison.
In addition I did some work to ensure that the planner won't think that an
array type is hashable unless its element type is hashable, and similarly
for sorting. This includes adding a datatype parameter to op_hashjoinable
and op_mergejoinable, and adding an explicit "hashable" flag to
SortGroupClause. The lack of a cross-check on the element type was a
pre-existing bug in mergejoin support --- but it didn't matter so much
before, because if you couldn't sort the element type there wasn't any good
alternative to failing anyhow. Now that we have the alternative of hashing
the array type, there are cases where we can avoid a failure by being picky
at the planner stage, so it's time to be picky.
The issue of exactly how to combine the per-element hash values to produce
an array hash is still open for discussion, but the rest of this is pretty
solid, so I'll commit it as-is.
Simon Riggs
Heikki Linnakangas
Andrew Dunstan
Magnus Hagander
Peter Eisentraut
Tom Lane
Robert Haas
Itagaki Takahiro
Bruce Momjian
Alvaro Herrera