be part of multixacts, so allocate a slot for each prepared transaction in
the "oldest member" array in multixact.c. On PREPARE TRANSACTION, transfer
the oldest member value from the current backends slot to the prepared xact
slot. Also save and recover the value from the 2pc state file.
The symptom of the bug was that after a transaction prepared, a shared lock
still held by the prepared transaction was sometimes ignored by other
transactions.
Fix back to 8.1, where both 2PC and multixact were introduced.
We have used -w for a long time as a means of reducing the reported diff
volume when one element of a result table isn't of the expected width.
However, most of the time the results just pass anyway, so this isn't as
important as it once was. Meanwhile, the risk of missing potentially
significant deviations has gone up, particularly with psql's ability to
report error cursor positions. So, let's switch over to space-sensitive
comparisons. Per my proposal of yesterday.
(All the expected files that I can test here seem to be ready for this
already, but we'll see what the buildfarm thinks about others.)
in the formerly-always-blank columns just to left and right of the data.
Different marking is used for a line break caused by a newline in the data
than for a straight wraparound. A newline break is signaled by a "+" in the
right margin column in ASCII mode, or a carriage return arrow in UNICODE mode.
Wraparound is signaled by a dot in the right margin as well as the following
left margin in ASCII mode, or an ellipsis symbol in the same places in UNICODE
mode. "\pset linestyle old-ascii" is added to make the previous behavior
available if anyone really wants it.
In passing, this commit also cleans up a few regression test files that
had unintended spacing differences from the current actual output.
Roger Leigh, reviewed by Gabrielle Roth and other members of PDXPUG.
list, minus a few specific words that have to be treated specially. This
replaces a hard-wired list of keywords that would have needed manual
maintenance, and was not getting it. The 8.4 coding was already missing
these words, causing ecpg to incorrectly treat them as reserved words:
CALLED, CATALOG, DEFINER, ENUM, FOLLOWING, INVOKER, OPTIONS, PARTITION,
PRECEDING, RANGE, SECURITY, SERVER, UNBOUNDED, WRAPPER. In HEAD we were
additionally missing COMMENTS, FUNCTIONS, SEQUENCES, TABLES.
Per gripe from Bosco Rama.
checked to determine whether the trigger should be fired.
For BEFORE triggers this is mostly a matter of spec compliance; but for AFTER
triggers it can provide a noticeable performance improvement, since queuing of
a deferred trigger event and re-fetching of the row(s) at end of statement can
be short-circuited if the trigger does not need to be fired.
Takahiro Itagaki, reviewed by KaiGai Kohei.
output filename if CSV logging was enabled and only one of the two possible
output files got rotated during a particular call (which would, in fact,
typically be the case during a size-based rotation). This would amount to
about MAXPGPATH (1KB) per rotation, and it's been there since the CSV
code was put in, so it's surprising that nobody noticed it before.
Per bug #5196 from Thomas Poindessous.
strength of database passwords, and create a sample implementation of
such a hook as a new contrib module "passwordcheck".
Laurenz Albe, reviewed by Takahiro Itagaki
adopted for EXPLAIN. This will allow additional options to be implemented
in future without having to make them fully-reserved keywords. The old syntax
remains available for existing options, however.
Itagaki Takahiro
non-Var sort/group expressions using ressortgroupref labels instead of
depending entirely on equal()-ity of the upper node's tlist expressions
to the lower node's. This avoids emitting the wrong outputs in cases
where there are textually identical volatile sort/group expressions,
as for example
select distinct random(),random() from generate_series(1,10);
Per report from Andrew Gierth.
Backpatch to 8.4. Arguably this is wrong all the way back, but the only known
case where there's an observable problem is when using hash aggregation to
implement DISTINCT, which is new as of 8.4. So for the moment I'll refrain
from backpatching further.
mergejoin to shield it from doing mark/restore and refetches. Put an explicit
flag in MergePath so we can centralize the logic that knows about this,
and add costing logic that considers using Materialize even when it's not
forced by the previously-existing considerations. This is in response to
a discussion back in August that suggested that materializing an inner
indexscan can be helpful when the refetch percentage is high enough.
default be "throw error on conflict", as per discussions. The GUC variable
is plpgsql.variable_conflict, with values "error", "use_variable",
"use_column". The behavior can also be specified per-function by inserting
one of
#variable_conflict error
#variable_conflict use_variable
#variable_conflict use_column
at the start of the function body.
The 8.5 release notes will need to mention using "use_variable" to retain
backward-compatible behavior, although we should encourage people to migrate
to the much less mistake-prone "error" setting.
Update the plpgsql documentation to match this and other recent changes.
but the transformed ArrayExpr claimed to have a return type of "domain",
even though the domain constraint was only checked by the enclosing
CoerceToDomain node. With this fix, the ArrayExpr is correctly labeled with
the base type of the domain. Per gripe by Tom Lane.
we need to check domain constraints. We used to do it correctly, but 8.4
introduced a separate code path for the "ARRAY[]::arraytype" case to infer
the type of an empty ARRAY construct from the cast target, and forgot to take
domains into account.
Per report from Florian G. Pflug.
User-defined consistent functions believes the check array
contains at least one true element which was not a true for
scanning pending list.
Per report from Yury Don <yura@vpcit.ru>
Per discussion, this should result in defaulting to SQL_ASCII encoding.
The original coding could not support that because it conflated selection
of SQL_ASCII encoding with not being able to determine the encoding.
Adjust pg_get_encoding_from_locale()'s API to distinguish these cases,
and fix callers appropriately. Only initdb actually changes behavior,
since the other callers were perfectly content to consider these cases
equivalent.
Per bug #5178 from Boh Yap. Not going to bother back-patching, since
no one has complained before and there's an easy workaround (namely,
specify the encoding you want).
directly. This was a lot of trouble, but should be worth it in terms of
not having to keep the plpgsql lexer in step with core anymore. In addition
the handling of keywords is significantly better-structured, allowing us to
de-reserve a number of words that plpgsql formerly treated as reserved.
The main motivation for this is that it's required for Informix compatibility
in ECPG.
This patch makes the ECPG and core grammars a bit closer to one another for
these productions.
Author: Zoltan Boszormenyi
mainloop.c. This ensures that postgres_fe.h is read before including
any system headers, which is necessary to avoid problems on some platforms
where we make nondefault selections of feature macros for stdio.h or
other headers. We have had this policy for flex modules in the backend
for many years, but for some reason it was not applied to psql.
Per trouble report from Alexandra Roy and diagnosis by Albe Laurenz.
Apple has fixed that bug in 10.6.2, and we should encourage users to
update to that version rather than trusting this cosmetic patch.
As was recently noted by Stephen Tyler, this patch was only masking
the problem in the context of DROP TABLESPACE, but the failure could
occur in other places such as pg_xlog cleanup.
In VACUUM FULL, an interrupt after the initial transaction has been recorded
as committed can cause postmaster to restart with the following error message:
PANIC: cannot abort transaction NNNN, it was already committed
This problem has been reported many times.
In lazy VACUUM, an interrupt after the table has been truncated by
lazy_truncate_heap causes other backends' relcache to still point to the
removed pages; this can cause future INSERT and UPDATE queries to error out
with the following error message:
could not read block XX of relation 1663/NNN/MMMM: read only 0 of 8192 bytes
The window to this race condition is extremely narrow, but it has been seen in
the wild involving a cancelled autovacuum process.
The solution for both problems is to inhibit interrupts in both operations
until after the respective transactions have been committed. It's not a
complete solution, because the transaction could theoretically be aborted by
some other error, but at least fixes the most common causes of both problems.
yytext. This is a necessary change if we're going to have a lexer interface
layer that does lookahead, since yytext won't necessarily be in step with
what the grammar thinks is the current token. yylval and yylloc should
be the only side-variables that we need to manage when doing lookahead.
of different parsers having different YYSTYPE unions that they want to use
with it. I defined a new union core_YYSTYPE that is just the (very short)
list of semantic values returned by the core scanner. I had originally
worried that this would require an extra interface layer, but actually we can
have parser.c's base_yylex (formerly filtered_base_yylex) take care of that at
no extra cost. Names associated with the core scanner are now "core_yy_foo",
with "base_yy_foo" being used in the core Bison parser and the parser.c
interface layer.
This solves the last serious stumbling block to eliminating plpgsql's separate
lexer. One restriction that will still be present is that plpgsql and the
core will have to agree on the token numbers assigned to tokens that can be
returned by the core lexer. Since Bison doesn't seem willing to accept
external assignments of those numbers, we'll have to live with decreeing that
core and plpgsql grammars declare these tokens first and in the same order.
can be the name of a plpgsql cursor variable, which formerly was converted
to $N before the core parser saw it, but that's no longer the case.
Deal with plain name references to plpgsql variables, and add a regression
test case that exposes the failure.
like the core parser's code. In particular, track locations at the character
rather than line level during parsing, allowing many more parse-time error
conditions to be reported with precise error pointers rather than just
"near line N".
Also, exploit the fact that we no longer need to substitute $N for variable
references by making extracted SQL queries and expressions be exact copies
of subranges of the function text, rather than having random whitespace
changes within them. This makes it possible to directly map parse error
positions from the core parser onto positions in the function text, which
lets us report them without the previous kluge of showing the intermediate
internal-query form. (Later it might be good to do that for core
parse-analysis errors too, but this patch is just touching plpgsql's
lexer/parser, not what happens at runtime.)
In passing, make plpgsql's lexer use palloc not malloc.
These changes make plpgsql's parse-time error reports noticeably nicer
(as illustrated by the regression test changes), and will also simplify
the planned removal of plpgsql's separate lexer by reducing the impedance
mismatch between what it does and what the core lexer does.
* Pull the responsibility for %TYPE and %ROWTYPE out of the scanner,
letting read_datatype manage it instead.
* Avoid unnecessary scanner-driven lookups of plpgsql variables in
places where it's not needed, which is actually most of the time;
we do not need it in DECLARE sections nor in text that is a SQL
query or expression.
* Rationalize the set of token types returned by the scanner:
distinguishing T_SCALAR, T_RECORD, T_ROW seems to complicate the grammar
in more places than it simplifies it, so merge these into one
token type T_DATUM; but split T_ERROR into T_DBLWORD and T_TRIPWORD
for clarity and simplicity of later processing.
Some of this will need to be revisited again when we try to make
plpgsql use the core scanner, but this patch gets some of the bigger
stumbling blocks out of the way.
into SQL expressions, to using the newly added parser callback hooks.
This allows us to do the substitutions in a more semantically-aware way:
a variable reference will only be recognized where it can validly go,
ie, a place where a column value or parameter would be legal, instead of
the former behavior that would replace any textual match including
table names and column aliases (leading to syntax errors later on).
A release-note-worthy fine point is that plpgsql variable names that match
fully-reserved words will now need to be quoted.
This commit preserves the former behavior that variable references take
precedence over any possible match to a column name. The infrastructure
is in place to support the reverse precedence or throwing an error on
ambiguity, but those behaviors aren't accessible yet.
Most of the code changes here are associated with making the namespace
data structure persist so that it can be consulted at runtime, instead
of throwing it away at the end of initial function parsing.
The plpgsql scanner is still doing name lookups, but that behavior is
now irrelevant for SQL expressions. A future commit will deal with
removing unnecessary lookups.
it works just as well to have them be ordinary identifiers, and this gets rid
of a number of ugly special cases. Plus we aren't interfering with non-rule
usage of these names.
catversion bump because the names change internally in stored rules.
behavior, and is so little used that no one has been interested in fixing it.
To ensure that possible uses are covered, remove the ALIAS declaration's
arbitrary restriction that only $n identifiers can be aliased.
(We could alternatively make RENAME act just like ALIAS, but per discussion
having two different ways to do the same thing is probably more confusing than
helpful.)
that are not handled by find_coercion_pathway, notably composite->RECORD.
Now that 8.4 supports composites as primary keys, it's worth dealing with
this case.
tarballs under 100 characters. This should avoid failures with certain
untarring tools (WinZip and Midnight Commander have been mentioned as
likely suspects). Per my proposal of yesterday.
catversion bumped since the initial contents of pg_proc change.
at the first keyword of the expression, rather than drawing a rather
artificial distinction between the ESCAPE subclause and the rest.
Per gripe from Gokulakannan Somasundaram and subsequent discusssion.
As proof of concept, modify plpgsql to use the hooks. plpgsql is still
inserting $n symbols textually, but the "back end" of the parsing process now
goes through the ParamRef hook instead of using a fixed parameter-type array,
and then execution only fetches actually-referenced parameters, using a hook
added to ParamListInfo.
Although there's a lot left to be done in plpgsql, this already cures the
"if (TG_OP = 'INSERT' and NEW.foo ...)" problem, as illustrated by the
changed regression test.
In PLy_output(), when the elog() call in the TRY branch throws an exception
(this can happen when a statement timeout kicks in, for example), the
PyErr_SetString() call in the CATCH branch can cause a segfault, because the
Py_XDECREF(so) call before it releases memory that is still used by the sv
variable that PyErr_SetString() uses as argument, because sv points into
memory owned by so.
Backpatched back to 8.0, where this code was introduced.
I also threw in a couple of volatile declarations for variables that are used
before and after the TRY. I don't think they caused the crash that I
observed, but they could become issues.
that it can scribble on scan->xs_ctup.t_self while following HOT chains,
so we can't rely on that to stay valid between hashgettuple() calls.
Introduce a private variable in HashScanOpaque, instead.
hash indexes keep entries sorted by hash value. First, the original plans for
concurrency assumed that insertions would happen only at the end of a page,
which is no longer true; this could cause scans to transiently fail to find
index entries in the presence of concurrent insertions. We can compensate
by teaching scans to re-find their position after re-acquiring read locks.
Second, neither the bucket split nor the bucket compaction logic had been
fixed to preserve hashvalue ordering, so application of either of those
processes could lead to permanent corruption of an index, in the sense
that searches might fail to find entries that are present.
This patch fixes the split and compaction logic to preserve hashvalue
ordering, but it cannot do anything about pre-existing corruption. We will
need to recommend reindexing all hash indexes in the 8.4.2 release notes.
To buy back the performance loss hereby induced in split and compaction,
fix them to use PageIndexMultiDelete instead of retail PageIndexDelete
operations. We might later want to do something with qsort'ing the
page contents rather than doing a binary search for each insertion,
but that seemed more invasive than I cared to risk in a back-patch.
Per bug #5157 from Jeff Janes and subsequent investigation.
recent proposal. As proof of concept, remove knowledge of Params from the
core parser, arranging for them to be handled entirely by parser hook
functions. It turns out we need an additional hook for that --- I had
forgotten about the code that handles inferring a parameter's type from
context.
This is a preliminary step towards letting plpgsql handle its variables
through parser hooks. Additional work remains to be done to expose the
facility through SPI, but I think this is all the changes needed in the core
parser.
The original coding ensured nbuckets and nbatch didn't exceed INT_MAX,
which while not insane on its own terms did nothing to protect subsequent
code like "palloc(nbatch * sizeof(BufFile *))". Since enormous join size
estimates might well be planner error rather than reality, it seems best
to constrain the initial sizes to be not more than work_mem/sizeof(pointer),
thus ensuring the allocated arrays don't exceed work_mem. We will allow
nbatch to get bigger than that during subsequent ExecHashIncreaseNumBatches
calls, but we should still guard against integer overflow in those palloc
requests. Per bug #5145 from Bernt Marius Johnsen.
Although the given test case only seems to fail back to 8.2, previous
releases have variants of this issue, so patch all supported branches.
adding the ModifyTable node type --- I had been thinking ModifyTable should
replace Append as a special case in push_plan(), but actually both of them
have to be special-cased.
when FOR UPDATE is propagated down into a sub-select expanded from a view.
Similar bug to parser's isLockedRel issue that I fixed yesterday; likewise
seems not quite worth the effort to back-patch.
underneath the Limit node, not atop it. This fixes the old problem that such
a query might unexpectedly return fewer rows than the LIMIT says, due to
LockRows discarding updated rows.
There is a related problem that LockRows might destroy the sort ordering
produced by earlier steps; but fixing that by pushing LockRows below Sort
would create serious performance problems that are unjustified in many
real-world applications, as well as potential deadlock problems from locking
many more rows than expected. Instead, keep the present semantics of applying
FOR UPDATE after ORDER BY within a single query level; but allow the user to
specify the other way by writing FOR UPDATE in a sub-select. To make that
work, track whether FOR UPDATE appeared explicitly in sub-selects or got
pushed down from the parent, and don't flatten a sub-select that contained an
explicit FOR UPDATE.
that it's called within an AfterTriggerBeginQuery/AfterTriggerEndQuery pair.
The RI cascade triggers suppress that overhead on the assumption that they
are always run non-deferred, so it's possible to violate the condition if
someone mistakenly changes pg_trigger to mark such a trigger deferred.
We don't really care about supporting that, but throwing an error instead
of crashing seems desirable. Per report from Marcelo Costa.
for example in
WITH w AS (SELECT * FROM foo) SELECT * FROM w, bar ... FOR UPDATE
the FOR UPDATE will now affect bar but not foo. This is more useful and
consistent than the original 8.4 behavior, which tried to propagate FOR UPDATE
into the WITH query but always failed due to assorted implementation
restrictions. Even though we are in process of removing those restrictions,
it seems correct on philosophical grounds to not let the outer query's
FOR UPDATE affect the WITH query.
In passing, fix isLockedRel which frequently got things wrong in
nested-subquery cases: "FOR UPDATE OF foo" applies to an alias foo in the
current query level, not subqueries. This has been broken for a long time,
but it doesn't seem worth back-patching further than 8.4 because the actual
consequences are minimal. At worst the parser would sometimes get
RowShareLock on a relation when it should be AccessShareLock or vice versa.
That would only make a difference if someone were using ExclusiveLock
concurrently, which no standard operation does, and anyway FOR UPDATE
doesn't result in visible changes so it's not clear that the someone would
notice any problem. Between that and the fact that FOR UPDATE barely works
with subqueries at all in existing releases, I'm not excited about worrying
about it.
those accepted by date_in(). I confused julian day numbers and number of
days since the postgres epoch 2000-01-01 in the original patch.
I just noticed that it's still easy to get such out-of-range values into
the database using to_date or +- operators, but this patch doesn't do
anything about those functions.
Per report from James Pye.
a lot of strange behaviors that occurred in join cases. We now identify the
"current" row for every joined relation in UPDATE, DELETE, and SELECT FOR
UPDATE/SHARE queries. If an EvalPlanQual recheck is necessary, we jam the
appropriate row into each scan node in the rechecking plan, forcing it to emit
only that one row. The former behavior could rescan the whole of each joined
relation for each recheck, which was terrible for performance, and what's much
worse could result in duplicated output tuples.
Also, the original implementation of EvalPlanQual could not re-use the recheck
execution tree --- it had to go through a full executor init and shutdown for
every row to be tested. To avoid this overhead, I've associated a special
runtime Param with each LockRows or ModifyTable plan node, and arranged to
make every scan node below such a node depend on that Param. Thus, by
signaling a change in that Param, the EPQ machinery can just rescan the
already-built test plan.
This patch also adds a prohibition on set-returning functions in the
targetlist of SELECT FOR UPDATE/SHARE. This is needed to avoid the
duplicate-output-tuple problem. It seems fairly reasonable since the
other restrictions on SELECT FOR UPDATE are meant to ensure that there
is a unique correspondence between source tuples and result tuples,
which an output SRF destroys as much as anything else does.
style by default. Per discussion, there seems to be hardly anything that
really relies on being able to change the regex flavor, so the ability to
select it via embedded options ought to be enough for any stragglers.
Also, if we didn't remove the GUC, we'd really be morally obligated to
mark the regex functions non-immutable, which'd possibly create performance
issues.
Per recent discussion, add_missing_from has been deprecated for long enough to
consider removing, and it's getting in the way of planned parser refactoring.
The system now always behaves as though add_missing_from were OFF.
pam_message array contains exactly one PAM_PROMPT_ECHO_OFF message.
Instead, deal with however many messages there are, and don't throw error
for PAM_ERROR_MSG and PAM_TEXT_INFO messages. This logic is borrowed from
openssh 5.2p1, which hopefully has seen more real-world PAM usage than we
have. Per bug #5121 from Ryan Douglas, which turned out to be caused by
the conv_proc being called with zero messages. Apparently that is normal
behavior given the combination of Linux pam_krb5 with MS Active Directory
as the domain controller.
Patch all the way back, since this code has been essentially untouched
since 7.4. (Surprising we've not heard complaints before.)
are named in the UPDATE's SET list.
Note: the schema of pg_trigger has not actually changed; we've just started
to use a column that was there all along. catversion bumped anyway so that
this commit is included in the history of potentially interesting changes
to system catalog contents.
Itagaki Takahiro
and SSPI athentication methods. While the old 2000 byte limit was more than
enough for Unix Kerberos implementations, tickets issued by Windows Domain
Controllers can be much larger.
Ian Turner
ASCII-art style of table output to be upgraded to use Unicode box drawing
characters if desired. By default, psql will use the Unicode characters
whenever client_encoding is UTF8.
The patch forces linestyle=ascii in pg_regress usage, ensuring we don't
break the regression tests in Unicode locales.
Roger Leigh
Also insert a couple of Asserts that check for stack overflow.
Bogus coding appears to be new in 8.4 --- older releases had a much
simpler algorithm here. Per bug #5111.
Michael Meskes
Tom Lane
Magnus Hagander
Heikki Linnakangas
Peter Eisentraut
Teodor Sigaev
Alvaro Herrera
Bruce Momjian
Andrew Dunstan