Use the CommitDate not the AuthorDate, as the former is representative of
the order in which things went into the main repository, and the latter
isn't very; we now have instances where the AuthorDate is as much as a
month before the patch really went in. Also, get rid of the "commit order
inversions" heuristic, which turns out not to do anything very desirable.
Instead we just print commits in strict timestamp order, interpreting the
"timestamp" of a merged commit as its timestamp on the newest branch it
appears in. This fixes some cases where very ancient commits were being
printed relatively early in the report.
The uniqueness condition might fail to hold intra-transaction, and assuming
it does can give incorrect query results. Per report from Marti Raudsepp,
though this is not his proposed patch.
Back-patch to 9.0, where both these features were introduced. In the
released branches, add the new IndexOptInfo field to the end of the struct,
to try to minimize ABI breakage for third-party code that may be examining
that struct.
A transaction can export a snapshot with pg_export_snapshot(), and then
others can import it with SET TRANSACTION SNAPSHOT. The data does not
leave the server so there are not security issues. A snapshot can only
be imported while the exporting transaction is still running, and there
are some other restrictions.
I'm not totally convinced that we've covered all the bases for SSI (true
serializable) mode, but it works fine for lesser isolation modes.
Joachim Wieland, reviewed by Marko Tiikkaja, and rather heavily modified
by Tom Lane
No need to do "errcode(errcode_for_file_access())", just
"errcode_for_file_access()" is enough. The extra errcode() call is useless
but harmless, so there's no user-visible bug here. Nevertheless, backpatch
to 9.1 where this code were added.
Avoid possibly dumping core when pgstat_track_activity_query_size has a
less-than-default value; avoid uselessly searching for the query string
of a successfully-exited backend; don't bother putting out an ERRDETAIL if
we don't have a query to show; some other minor stylistic improvements.
Turns out that use of ShareUpdateExclusiveLock or ShareRowExclusiveLock
to protect DDL changes had gotten copied into several places that were
not touched by either of Simon's original patches for the feature, and
thus neither he nor I thought to revert them. (Indeed, it appears that
two of these uses were committed *after* the reversion, which just goes
to show that git merging is no panacea.) Change these places to use
AccessExclusiveLock again. If we ever manage to resurrect that feature,
we're going to have to think a bit harder about how to keep lock level
usage in sync for DDL operations that aren't within the AlterTable
infrastructure.
Two of these bugs are only in HEAD, but one is in the 9.1 branch too.
Alvaro found one of them, I found the other two.
To avoid minimize risk inside the postmaster, we subject this feature
to a number of significant limitations. We very much wish to avoid
doing any complex processing inside the postmaster, due to the
posssibility that the crashed backend has completely corrupted shared
memory. To that end, no encoding conversion is done; instead, we just
replace anything that doesn't look like an ASCII character with a
question mark. We limit the amount of data copied to 1024 characters,
and carefully sanity check the source of that data. While these
restrictions would doubtless be unacceptable in a general-purpose
logging facility, even this limited facility seems like an improvement
over the status quo ante.
Marti Raudsepp, reviewed by PDXPUG and myself
Essentially, the "IF EXISTS" portion was being ignored, and an error
thrown anyway if the opfamily did not exist.
I broke this in commit fd1843ff8979c0461fb3f1a9eab61140c977e32d; so
backpatch to 9.1.X.
Report and diagnosis by KaiGai Kohei.
There's no need to clamp the standby's xmin to be greater than
GetOldestXmin's result; if there were any such need this logic would be
hopelessly inadequate anyway, because it fails to account for
within-database versus cluster-wide values of GetOldestXmin. So get rid of
that, and just rely on sanity-checking that the xmin is not wrapped around
relative to the nextXid counter. Also, don't reset the walsender's xmin if
the current feedback xmin is indeed out of range; that just creates more
problems than we already had. Lastly, don't bother to take the
ProcArrayLock; there's no need to do that to set xmin.
Also improve the comments about this in GetOldestXmin itself.
Make it return empty strings when there are no more words to the left of
the current position, instead of sometimes returning NULL and other times
returning copies of the leftmost word. Also, fetch the words in one scan,
rather than the previous wasteful approach of starting from scratch for
each word. Make the code a bit harder to break when someone decides we
need more words of context, too. (There was actually a memory leak here,
because whoever added prev6_wd neglected to free it.)
extnamespace means something altogether different in this context.
Mostly by accident, this coding error (introduced in my commit
82a4a777d9) broke the buildfarm instead
of just silently doing the wrong thing.
This gets rid of a significant amount of duplicative code.
KaiGai Kohei, reviewed in earlier versions by Dimitri Fontaine, with
further review and cleanup by me.
This is merely an exercise in satisfying pedants, not a bug fix, because
in every case we were checking for failure later with ferror(), or else
there was nothing useful to be done about a failure anyway. Document
the latter cases.
An empty HBA file is surely an error, since it means there is no way to
connect to the server. We've not heard identifiable reports of people
actually doing that, but this will also close off the case Thom Brown just
complained of, namely pointing hba_file at a directory. (On at least some
platforms with some directories, it will read as an empty file.)
Perhaps this should be back-patched, but given the lack of previous
complaints, I won't add extra work for the translators.
There's no particular value in doing AssertMacro((tup) != NULL) in front
of code that's certain to crash anyway if tup is NULL. And if "tup" is
actually the address of a local variable, gcc 4.6 whinges about it. That's
arguably pretty broken on gcc's part, but we might as well remove the
useless test to silence the warnings. This gets rid of all the -Waddress
warnings in the backend; there are some in libpq and psql that are a bit
harder to avoid.
The heuristic for when to dump a cast failed for a cast between table
rowtypes, as reported by Frédéric Rejol. Fix it by setting
the "dump" flag for such a type the same way as the flag is set for the
underlying table or base type. This won't result in the auto-generated
type appearing in the output, since setting its objType to DO_DUMMY_TYPE
unconditionally suppresses that. But it will result in dumpCast doing what
was intended.
Back-patch to 8.3. The 8.2 code is rather different in this area, and it
doesn't seem worth any risk to fix a corner case that nobody has stumbled
on before.
In general the data returned by an index-only scan should have the
datatypes originally computed by FormIndexDatum. If the index opclasses
use "storage" datatypes different from their input datatypes, the scan
tuple will not have the same rowtype attributed to the index; but we had
a hard-wired assumption that that was true in nodeIndexonlyscan.c. We'd
already hacked around the issue for the one case where the types are
different in btree indexes (btree name_ops), but this would definitely
come back to bite us if we ever implement index-only scans in GiST.
To fix, require the index AM to explicitly provide the tupdesc for the
tuple it is returning. btree can just pass back the index's tupdesc, but
GiST will have to work harder when and if it supports index-only scans.
I had previously proposed fixing this by allowing the index AM to fill the
scan tuple slot directly; but on reflection that seemed like a module
layering violation, since TupleTableSlots are creatures of the executor.
At least in the btree case, it would also be less efficient, since the
tuple deconstruction work would occur even for rows later found to be
invisible to the scan's snapshot.
Rearrange text to improve clarity, and add an example of implicit reference
to a plpgsql variable in a bound cursor's query. Byproduct of some work
I'd done on the "named cursor parameters" patch before giving up on it.
This view was being insufficiently careful about matching the FK constraint
to the depended-on primary or unique key constraint. That could result in
failure to show an FK constraint at all, or showing it multiple times, or
claiming that it depended on a different constraint than the one it really
does. Fix by joining via pg_depend to ensure that we find only the correct
dependency.
Back-patch, but don't bump catversion because we can't force initdb in back
branches. The next minor-version release notes should explain that if you
need to fix this in an existing installation, you can drop the
information_schema schema then re-create it by sourcing
$SHAREDIR/information_schema.sql in each database (as a superuser of
course).
Add a column pg_class.relallvisible to remember the number of pages that
were all-visible according to the visibility map as of the last VACUUM
(or ANALYZE, or some other operations that update pg_class.relpages).
Use relallvisible/relpages, instead of an arbitrary constant, to estimate
how many heap page fetches can be avoided during an index-only scan.
This is pretty primitive and will no doubt see refinements once we've
acquired more field experience with the index-only scan mechanism, but
it's way better than using a constant.
Note: I had to adjust an underspecified query in the window.sql regression
test, because it was changing answers when the plan changed to use an
index-only scan. Some of the adjacent tests perhaps should be adjusted
as well, but I didn't do that here.
This way, if a role's config setting uses the name of another role,
the validity of the dump isn't dependent on the order in which those
two roles are dumped.
Code by Phil Sorber, comment by me.
Nobody using the missing_ok flag yet, but let's speculate that this will
be a better interface for future callers.
KaiGai Kohei, with some adjustments by me.
This patch restores the pre-9.1 behavior that pl/perl functions returning
VOID ignore the result value of their last Perl statement. 9.1.0
unintentionally threw an error if the last statement returned a reference,
as reported by Amit Khandekar.
Also, make sure it works to return a string value for a composite type,
so long as the string meets the type's input format. We already allowed
the equivalent behavior for arrays, so it seems inconsistent to not allow
it for composites.
In addition, ensure we throw errors for attempts to return arrays or hashes
when the function's declared result type is not an array or composite type,
respectively. Pre-9.1 versions rather uselessly returned strings like
ARRAY(0x221a9a0) or HASH(0x221aa90), while 9.1.0 threw an error for the
hash case and returned a garbage value for the array case.
Also, clean up assorted grotty coding in Perl array conversion, including
use of a session-lifespan memory context to accumulate the array value
(resulting in session-lifespan memory leak on error), failure to apply the
declared typmod if any, and failure to detect some cases of non-rectangular
multi-dimensional arrays.
Alex Hunsaker and Tom Lane
Relation rowtypes and automatically-generated array types do not need to
have their own extension membership dependency entries. If we create such
then it becomes more difficult to remove items from an extension, and it's
also harder for an extension upgrade script to make sure it duplicates the
dependencies created by the extension's regular installation script.
I changed the code in such a way that this happened in commit
988cccc620, I think because of worries about
the shell-type-replacement case; but that cure was worse than the disease.
It would only matter if one extension created a shell type that was
replaced with an auto-generated type in another extension, which seems
pretty far-fetched. Better to make this work unsurprisingly in normal
cases.
Report and patch by Robert Haas, comment adjustments by me.
We have seen one too many reports of people trying to use 9.1 extension
files in the old-fashioned way of sourcing them in psql. Not only does
that usually not work (due to failure to substitute for MODULE_PATHNAME
and/or @extschema@), but if it did work they'd get a collection of loose
objects not an extension. To prevent this, insert an \echo ... \quit
line that prints a suitable error message into each extension script file,
and teach commands/extension.c to ignore lines starting with \echo.
That should not only prevent any adverse consequences of loading a script
file the wrong way, but make it crystal clear to users that they need to
do it differently now.
Tom Lane, following an idea of Andrew Dunstan's. Back-patch into 9.1
... there is not going to be much value in this if we wait till 9.2.
The documentation neglected to explain its behavior in a script file
(it only ends execution of the script, not psql as a whole), and failed
to mention the long form \quit either.
