compute_tsvector_stats() detoasted and kept in memory every tsvector value
in the sample, but that can be a lot of memory. The original bug report
described a case using over 10 gigabytes, with statistics target of 10000
(the maximum).
To fix, allocate a separate copy of just the lexemes that we keep around,
and free the detoasted tsvector values as we go. This adds some palloc/pfree
overhead, when you have a lot of distinct lexemes in the sample, but it's
better than running out of memory.
Fixes bug #14654 reported by James C. Reviewed by Tom Lane. Backport to
all supported versions.
Discussion: https://www.postgresql.org/message-id/20170514200602.1451.46797@wrigleys.postgresql.org
Don't move parenthesized lines to the left, even if that means they
flow past the right margin.
By default, BSD indent lines up statement continuation lines that are
within parentheses so that they start just to the right of the preceding
left parenthesis. However, traditionally, if that resulted in the
continuation line extending to the right of the desired right margin,
then indent would push it left just far enough to not overrun the margin,
if it could do so without making the continuation line start to the left of
the current statement indent. That makes for a weird mix of indentations
unless one has been completely rigid about never violating the 80-column
limit.
This behavior has been pretty universally panned by Postgres developers.
Hence, disable it with indent's new -lpl switch, so that parenthesized
lines are always lined up with the preceding left paren.
This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
Change pg_bsd_indent to follow upstream rules for placement of comments
to the right of code, and remove pgindent hack that caused comments
following #endif to not obey the general rule.
Commit e3860ffa4d wasn't actually using
the published version of pg_bsd_indent, but a hacked-up version that
tried to minimize the amount of movement of comments to the right of
code. The situation of interest is where such a comment has to be
moved to the right of its default placement at column 33 because there's
code there. BSD indent has always moved right in units of tab stops
in such cases --- but in the previous incarnation, indent was working
in 8-space tab stops, while now it knows we use 4-space tabs. So the
net result is that in about half the cases, such comments are placed
one tab stop left of before. This is better all around: it leaves
more room on the line for comment text, and it means that in such
cases the comment uniformly starts at the next 4-space tab stop after
the code, rather than sometimes one and sometimes two tabs after.
Also, ensure that comments following #endif are indented the same
as comments following other preprocessor commands such as #else.
That inconsistency turns out to have been self-inflicted damage
from a poorly-thought-through post-indent "fixup" in pgindent.
This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
The new indent version includes numerous fixes thanks to Piotr Stefaniak.
The main changes visible in this commit are:
* Nicer formatting of function-pointer declarations.
* No longer unexpectedly removes spaces in expressions using casts,
sizeof, or offsetof.
* No longer wants to add a space in "struct structname *varname", as
well as some similar cases for const- or volatile-qualified pointers.
* Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely.
* Fixes bug where comments following declarations were sometimes placed
with no space separating them from the code.
* Fixes some odd decisions for comments following case labels.
* Fixes some cases where comments following code were indented to less
than the expected column 33.
On the less good side, it now tends to put more whitespace around typedef
names that are not listed in typedefs.list. This might encourage us to
put more effort into typedef name collection; it's not really a bug in
indent itself.
There are more changes coming after this round, having to do with comment
indentation and alignment of lines appearing within parentheses. I wanted
to limit the size of the diffs to something that could be reviewed without
one's eyes completely glazing over, so it seemed better to split up the
changes as much as practical.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
Reformat various places in which pgindent will make a mess, and
fix a few small violations of coding style that I happened to notice
while perusing the diffs from a pgindent dry run.
There is one actual bug fix here: the need-to-enlarge-the-buffer code
path in icu_convert_case was obviously broken. Perhaps it's unreachable
in our usage? Or maybe this is just sadly undertested.
The mess cleaned up in commit da0759600 is clear evidence that it's a
bug hazard to expect the caller of get_attstatsslot()/free_attstatsslot()
to provide the correct type OID for the array elements in the slot.
Moreover, we weren't even getting any performance benefit from that,
since get_attstatsslot() was extracting the real type OID from the array
anyway. So we ought to get rid of that requirement; indeed, it would
make more sense for get_attstatsslot() to pass back the type OID it found,
in case the caller isn't sure what to expect, which is likely in binary-
compatible-operator cases.
Another problem with the current implementation is that if the stats array
element type is pass-by-reference, we incur a palloc/memcpy/pfree cycle
for each element. That seemed acceptable when the code was written because
we were targeting O(10) array sizes --- but these days, stats arrays are
almost always bigger than that, sometimes much bigger. We can save a
significant number of cycles by doing one palloc/memcpy/pfree of the whole
array. Indeed, in the now-probably-common case where the array is toasted,
that happens anyway so this method is basically free. (Note: although the
catcache code will inline any out-of-line toasted values, it doesn't
decompress them. At the other end of the size range, it doesn't expand
short-header datums either. In either case, DatumGetArrayTypeP would have
to make a copy. We do end up using an extra array copy step if the element
type is pass-by-value and the array length is neither small enough for a
short header nor large enough to have suffered compression. But that
seems like a very acceptable price for winning in pass-by-ref cases.)
Hence, redesign to take these insights into account. While at it,
convert to an API in which we fill a struct rather than passing a bunch
of pointers to individual output arguments. That will make it less
painful if we ever want further expansion of what get_attstatsslot can
pass back.
It's certainly arguable that this is new development and not something to
push post-feature-freeze. However, I view it as primarily bug-proofing
and therefore something that's better to have sooner not later. Since
we aren't quite at beta phase yet, let's put it in.
Discussion: https://postgr.es/m/16364.1494520862@sss.pgh.pa.us
This makes almost all core code follow the policy introduced in the
previous commit. Specific decisions:
- Text search support functions with char* and length arguments, such as
prsstart and lexize, may receive unaligned strings. I doubt
maintainers of non-core text search code will notice.
- Use plain VARDATA() on values detoasted or synthesized earlier in the
same function. Use VARDATA_ANY() on varlenas sourced outside the
function, even if they happen to always have four-byte headers. As an
exception, retain the universal practice of using VARDATA() on return
values of SendFunctionCall().
- Retain PG_GETARG_BYTEA_P() in pageinspect. (Page images are too large
for a one-byte header, so this misses no optimization.) Sites that do
not call get_page_from_raw() typically need the four-byte alignment.
- For now, do not change btree_gist. Its use of four-byte headers in
memory is partly entangled with storage of 4-byte headers inside
GBT_VARKEY, on disk.
- For now, do not change gtrgm_consistent() or gtrgm_distance(). They
incorporate the varlena header into a cache, and there are multiple
credible implementation strategies to consider.
Gen_fmgrtab.pl creates a new file fmgrprotos.h, which contains
prototypes for all functions registered in pg_proc.h. This avoids
having to manually maintain these prototypes across a random variety of
header files. It also automatically enforces a correct function
signature, and since there are warnings about missing prototypes, it
will detect functions that are defined but not registered in
pg_proc.h (or otherwise used).
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
I got frustrated by the lack of commentary in this area, so here is some
reverse-engineered documentation, along with minor stylistic cleanup.
No code changes more significant than removal of unused variables.
Back-patch to 9.6, not because that's useful in itself, but because
we have some bugs to fix in phrase search and this would cause merge
failures if it's only in HEAD.
I found that half a dozen (nearly 5%) of our AllocSetContextCreate calls
had typos in the context-sizing parameters. While none of these led to
especially significant problems, they did create minor inefficiencies,
and it's now clear that expecting people to copy-and-paste those calls
accurately is not a great idea. Let's reduce the risk of future errors
by introducing single macros that encapsulate the common use-cases.
Three such macros are enough to cover all but two special-purpose contexts;
those two calls can be left as-is, I think.
While this patch doesn't in itself improve matters for third-party
extensions, it doesn't break anything for them either, and they can
gradually adopt the simplified notation over time.
In passing, change TopMemoryContext to use the default allocation
parameters. Formerly it could only be extended 8K at a time. That was
probably reasonable when this code was written; but nowadays we create
many more contexts than we did then, so that it's not unusual to have a
couple hundred K in TopMemoryContext, even without considering various
dubious code that sticks other things there. There seems no good reason
not to let it use growing blocks like most other contexts.
Back-patch to 9.6, mostly because that's still close enough to HEAD that
it's easy to do so, and keeping the branches in sync can be expected to
avoid some future back-patching pain. The bugs fixed by these changes
don't seem to be significant enough to justify fixing them further back.
Discussion: <21072.1472321324@sss.pgh.pa.us>
If ANALYZE found no repeated non-null entries in its sample, it set the
column's stadistinct value to -1.0, intending to indicate that the entries
are all distinct. But what this value actually means is that the number
of distinct values is 100% of the table's rowcount, and thus it was
overestimating the number of distinct values by however many nulls there
are. This could lead to very poor selectivity estimates, as for example
in a recent report from Andreas Joseph Krogh. We should discount the
stadistinct value by whatever we've estimated the nulls fraction to be.
(That is what will happen if we choose to use a negative stadistinct for
a column that does have repeated entries, so this code path was just
inconsistent.)
In addition to fixing the stadistinct entries stored by several different
ANALYZE code paths, adjust the logic where get_variable_numdistinct()
forces an "all distinct" estimate on the basis of finding a relevant unique
index. Unique indexes don't reject nulls, so there's no reason to assume
that the null fraction doesn't apply.
Back-patch to all supported branches. Back-patching is a bit of a judgment
call, but this problem seems to affect only a few users (else we'd have
identified it long ago), and it's bad enough when it does happen that
destabilizing plan choices in a worse direction seems unlikely.
Patch by me, with documentation wording suggested by Dean Rasheed
Report: <VisenaEmail.26.df42f82acae38a58.156463942b8@tc7-visena>
Discussion: <16143.1470350371@sss.pgh.pa.us>
Mostly these are just comments but there are a few in documentation
and a handful in code and tests. Hopefully this doesn't cause too much
unnecessary pain for backpatching. I relented from some of the most
common like "thru" for that reason. The rest don't seem numerous
enough to cause problems.
Thanks to Kevin Lyda's tool https://pypi.python.org/pypi/misspellings
These adjustments adjust code and comments in minor ways to prevent
pgindent from mangling them. Among other things, I tried to avoid
situations where pgindent would emit "a +b" instead of "a + b", and I
tried to avoid having it break up inline comments across multiple
lines.
Patch introduces new text search operator (<-> or <DISTANCE>) into tsquery.
On-disk and binary in/out format of tsquery are backward compatible.
It has two side effect:
- change order for tsquery, so, users, who has a btree index over tsquery,
should reindex it
- less number of parenthesis in tsquery output, and tsquery becomes more
readable
Authors: Teodor Sigaev, Oleg Bartunov, Dmitry Ivanov
Reviewers: Alexander Korotkov, Artur Zakirov
When tsearch was implemented I did several mistakes in hostname/email
definition rules:
1) allow underscore in hostname what prohibited by RFC
2) forget to allow leading digits separated by hyphen (like 123-x.com)
in hostname
3) do no allow underscore/hyphen after leading digits in localpart of email
Artur's patch resolves two last issues, but by the way allows hosts name like
123_x.com together with 123-x.com. RFC forbids underscore usage in hostname
but pg allows that since initial tsearch version in core, although only
for non-digits. Patch syncs support digits and nondigits in both hostname and
email.
Forbidding underscore in hostname may break existsing usage of tsearch and,
anyhow, it should be done by separate patch.
Author: Artur Zakirov
BUG: #13964
- allow to use non-ascii characters as affix flag. Non-numeric affix flags now
are stored as string instead of numeric value of character.
- allow to use 0 as affix flag in numeric encoded affixes
That adds support for arabian, hungarian, turkish and
brazilian portuguese languages.
Author: Artur Zakirov with heavy editorization by me
Some dictionaries have duplicated base words with different affix set, we
just merge that sets into one set. But previously merging of sets of affixes
was actually a concatenation of strings but it's wrong for numeric
representation of affixes because such representation uses comma to
separate affixes.
Author: Artur Zakirov
There were two places in spell.c that supposed that they could search
for a location in a string produced by lowerstr() and then transpose
the offset into the original string. But this fails completely if
lowerstr() transforms any characters into characters of different byte
length, as can happen in Turkish UTF8 for instance.
We'd added some comments about this coding in commit 51e78ab4ff,
but failed to realize that it was not merely confusing but wrong.
Coverity complained about this code years ago, but in such an opaque
fashion that nobody understood what it was on about. I'm not entirely
sure that this issue *is* what it's on about, actually, but perhaps
this patch will shut it up -- and in any case the problem is clear.
Back-patch to all supported branches.
isdigit(), isspace(), etc are likely to give surprising results if passed a
signed char. We should always cast the argument to unsigned char to avoid
that. Error in commit d78a7d9c7f, found by buildfarm member gaur.
Now it's possible to load recent version of Hunspell for several languages.
To handle these dictionaries Hunspell patch adds support for:
* FLAG long - sets the double extended ASCII character flag type
* FLAG num - sets the decimal number flag type (from 1 to 65535)
* AF parameter - alias for flag's set
Also it moves test dictionaries into separate directory.
Author: Artur Zakirov with editorization by me
It turns out that on FreeBSD-derived platforms (including OS X), the
*scanf() family of functions is pretty much brain-dead about multibyte
characters. In particular it will apply isspace() to individual bytes
of input even when those bytes are part of a multibyte character, thus
allowing false recognition of a field-terminating space.
We appear to have little alternative other than instituting a coding
rule that *scanf() is not to be used if the input string might contain
multibyte characters. (There was some discussion of relying on "%ls",
but that probably just moves the portability problem somewhere else,
and besides it doesn't fully prevent BSD *scanf() from using isspace().)
This patch is a down payment on that: it gets rid of use of sscanf()
to parse ispell dictionary files, which are certainly at great risk
of having a problem. The code is cleaner this way anyway, though
a bit longer.
In passing, improve a few comments.
Report and patch by Artur Zakirov, reviewed and somewhat tweaked by me.
Back-patch to all supported branches.
Use "a" and "an" correctly, mostly in comments. Two error messages were
also fixed (they were just elogs, so no translation work required). Two
function comments in pg_proc.h were also fixed. Etsuro Fujita reported one
of these, but I found a lot more with grep.
Also fix a few other typos spotted while grepping for the a/an typos.
For example, "consists out of ..." -> "consists of ...". Plus a "though"/
"through" mixup reported by Euler Taveira.
Many of these typos were in old code, which would be nice to backpatch to
make future backpatching easier. But much of the code was new, and I didn't
feel like crafting separate patches for each branch. So no backpatching.
In 83ff1618 we defined integer limits iff they're not provided by the
system. That turns out not to be the greatest idea because there's
different ways some datatypes can be represented. E.g. on OSX PG's 64bit
datatype will be a 'long int', but OSX unconditionally uses 'long
long'. That disparity then can lead to warnings, e.g. around printf
formats.
One way to fix that would be to back int64 using stdint.h's
int64_t. While a good idea it's not that easy to implement. We would
e.g. need to include stdint.h in our external headers, which we don't
today. Also computing the correct int64 printf formats in that case is
nontrivial.
Instead simply prefix the integer limits with PG_ and define them
unconditionally. I've adjusted all the references to them in code, but
not the ones in comments; the latter seems unnecessary to me.
Discussion: 20150331141423.GK4878@alap3.anarazel.de
Several submitted and even committed patches have run into the problem
that C89, our baseline, does not provide minimum/maximum values for
various integer datatypes. C99's stdint.h does, but we can't rely on
it.
Several parts of the code defined limits locally, so instead centralize
the definitions to c.h.
This patch also changes the more obvious usages of literal limit values;
there's more places that could be changed, but it's less clear whether
it's beneficial to change those.
Author: Andrew Gierth
Discussion: 87619tc5wc.fsf@news-spur.riddles.org.uk
dict_thesaurus stored phrase IDs in uint16 fields, so it would get confused
and even crash if there were more than 64K entries in the configuration
file. It turns out to be basically free to widen the phrase IDs to uint32,
so let's just do so.
This was complained of some time ago by David Boutin (in bug #7793);
he later submitted an informal patch but it was never acted on.
We now have another complaint (bug #11901 from Luc Ouellette) so it's
time to make something happen.
This is basically Boutin's patch, but for future-proofing I also added a
defense against too many words per phrase. Note that we don't need any
explicit defense against overflow of the uint32 counters, since before that
happens we'd hit array allocation sizes that repalloc rejects.
Back-patch to all supported branches because of the crash risk.
Don't crash if an ispell dictionary definition contains flags but not
any compound affixes. (This isn't a security issue since only superusers
can install affix files, but still it's a bad thing.)
Also, be more careful about detecting whether an affix-file FLAG command
is old-format (ispell) or new-format (myspell/hunspell). And change the
error message about mixed old-format and new-format commands into something
intelligible.
Per bug #11770 from Emre Hasegeli. Back-patch to all supported branches.
Additional non-security issues/improvements spotted by Coverity.
In backend/libpq, no sense trying to protect against port->hba being
NULL after we've already dereferenced it in the switch() statement.
Prevent against possible overflow due to 32bit arithmitic in
basebackup throttling (not yet released, so no security concern).
Remove nonsensical check of array pointer against NULL in procarray.c,
looks to be a holdover from 9.1 and earlier when there were pointers
being used but now it's just an array.
Remove pointer check-against-NULL in tsearch/spell.c as we had already
dereferenced it above (in the strcmp()).
Remove dead code from adt/orderedsetaggs.c, isnull is checked
immediately after each tuplesort_getdatum() call and if true we return,
so no point checking it again down at the bottom.
Remove recently added minor error-condition memory leak in pg_regress.
A large majority of the callers of pg_do_encoding_conversion were
specifying the database encoding as either source or target of the
conversion, meaning that we can use the less general functions
pg_any_to_server/pg_server_to_any instead.
The main advantage of using the latter functions is that they can make use
of a cached conversion-function lookup in the common case that the other
encoding is the current client_encoding. It's notationally cleaner too in
most cases, not least because of the historical artifact that the latter
functions use "char *" rather than "unsigned char *" in their APIs.
Note that pg_any_to_server will apply an encoding verification step in
some cases where pg_do_encoding_conversion would have just done nothing.
This seems to me to be a good idea at most of these call sites, though
it partially negates the performance benefit.
Per discussion of bug #9210.
Coverity identified a number of places in which it couldn't prove that a
string being copied into a fixed-size buffer would fit. We believe that
most, perhaps all of these are in fact safe, or are copying data that is
coming from a trusted source so that any overrun is not really a security
issue. Nonetheless it seems prudent to forestall any risk by using
strlcpy() and similar functions.
Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports.
In addition, fix a potential null-pointer-dereference crash in
contrib/chkpass. The crypt(3) function is defined to return NULL on
failure, but chkpass.c didn't check for that before using the result.
The main practical case in which this could be an issue is if libc is
configured to refuse to execute unapproved hashing algorithms (e.g.,
"FIPS mode"). This ideally should've been a separate commit, but
since it touches code adjacent to one of the buffer overrun changes,
I included it in this commit to avoid last-minute merge issues.
This issue was reported by Honza Horak.
Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
In p_isdigit and other character class test functions generated by the
p_iswhat macro, the code path for non-C locales with multibyte encodings
contained a bogus pointer cast that would accidentally fail to malfunction
if types wchar_t and wint_t have the same width. Apparently that is true
on most platforms, but not on recent Cygwin releases. Remove the cast,
as it seems completely unnecessary (I think it arose from a false analogy
to the need to cast to unsigned char when dealing with the <ctype.h>
functions). Per bug #8970 from Marco Atzeri.
In the same functions, the code path for C locale with a multibyte encoding
simply ANDed each wide character with 0xFF before passing it to the
corresponding <ctype.h> function. This could result in false positive
answers for some non-ASCII characters, so use a range test instead.
Noted by me while investigating Marco's complaint.
Also, remove some useless though not actually buggy maskings and casts
in the hand-coded p_isalnum and p_isalpha functions, which evidently
got tested a bit more carefully than the macro-generated functions.
These changes should generally improve correctness/maintainability.
A nice side benefit is that several kilobytes move from initialized
data to text segment, allowing them to be shared across processes and
probably reducing copy-on-write overhead while forking a new backend.
Unfortunately this doesn't seem to help libpq in the same way (at least
not when it's compiled with -fpic on x86_64), but we can hope the linker
at least collects all nominally-const data together even if it's not
actually part of the text segment.
Also, make pg_encname_tbl[] static in encnames.c, since there seems
no very good reason for any other code to use it; per a suggestion
from Wim Lewis, who independently submitted a patch that was mostly
a subset of this one.
Oskari Saarenmaa, with some editorialization by me
I made multiple errors in commit 97532f7c29,
stemming mostly from failure to think about the available frequency data
as being element frequencies not value frequencies (so that occurrences of
different elements are not mutually exclusive). This led to sillinesses
such as estimating that "word" would match more rows than "word:*".
The choice to clamp to a minimum estimate of DEFAULT_TS_MATCH_SEL also
seems pretty ill-considered in hindsight, as it would frequently result in
an estimate much larger than the available data suggests. We do need some
sort of clamp, since a pattern not matching any of the MCELEMs probably
still needs a selectivity estimate of more than zero. I chose instead to
clamp to at least what a non-MCELEM word would be estimated as, preserving
the property that "word:*" doesn't get an estimate less than plain "word",
whether or not the word appears in MCELEM.
Per investigation of a gripe from Bill Martin, though I suspect that his
example case actually isn't even reaching the erroneous code.
Back-patch to 9.1 where this code was introduced.
This reduces unnecessary exposure of other headers through htup.h, which
is very widely included by many files.
I have chosen to move the function prototypes to the new file as well,
because that means htup.h no longer needs to include tupdesc.h. In
itself this doesn't have much effect in indirect inclusion of tupdesc.h
throughout the tree, because it's also required by execnodes.h; but it's
something to explore in the future, and it seemed best to do the htup.h
change now while I'm busy with it.
Commit 3855968f32 added syntax, pg_dump,
psql support, and documentation, but the triggers didn't actually fire.
With this commit, they now do. This is still a pretty basic facility
overall because event triggers do not get a whole lot of information
about what the user is trying to do unless you write them in C; and
there's still no option to fire them anywhere except at the very
beginning of the execution sequence, but it's better than nothing,
and a good building block for future work.
Along the way, add a regression test for ALTER LARGE OBJECT, since
testing of event triggers reveals that we haven't got one.
Dimitri Fontaine and Robert Haas
The Solaris Studio compiler warns about these instances, unlike more
mainstream compilers such as gcc. But manual inspection showed that
the code is clearly not reachable, and we hope no worthy compiler will
complain about removing this code.
The latter was already the dominant use, and it's preferable because
in C the convention is that intXX means XX bits. Therefore, allowing
mixed use of int2, int4, int8, int16, int32 is obviously confusing.
Remove the typedefs for int2 and int4 for now. They don't seem to be
widely used outside of the PostgreSQL source tree, and the few uses
can probably be cleaned up by the time this ships.
This patch improves selectivity estimation for the array <@, &&, and @>
(containment and overlaps) operators. It enables collection of statistics
about individual array element values by ANALYZE, and introduces
operator-specific estimators that use these stats. In addition,
ScalarArrayOpExpr constructs of the forms "const = ANY/ALL (array_column)"
and "const <> ANY/ALL (array_column)" are estimated by treating them as
variants of the containment operators.
Since we still collect scalar-style stats about the array values as a
whole, the pg_stats view is expanded to show both these stats and the
array-style stats in separate columns. This creates an incompatible change
in how stats for tsvector columns are displayed in pg_stats: the stats
about lexemes are now displayed in the array-related columns instead of the
original scalar-related columns.
There are a few loose ends here, notably that it'd be nice to be able to
suppress either the scalar-style stats or the array-element stats for
columns for which they're not useful. But the patch is in good enough
shape to commit for wider testing.
Alexander Korotkov, reviewed by Noah Misch and Nathan Boley
This addresses only those cases that are easy to fix by adding or
moving a const qualifier or removing an unnecessary cast. There are
many more complicated cases remaining.
The previous coding would allow requests up to half of maxBlockSize to be
treated as "chunks", but when that actually did happen, we'd waste nearly
half of the space in the malloc block containing the chunk, if no smaller
requests came along to fill it. Avoid this scenario by limiting the
maximum size of a chunk to 1/8th maxBlockSize, so that we can waste no more
than 1/8th of the allocated space. This will not change the behavior at
all for the default context size parameters (with large maxBlockSize),
but it will change the behavior when using ALLOCSET_SMALL_MAXSIZE.
In particular, there's no longer a need for spell.c to be overly concerned
about the request size parameters it uses, so remove a rather unhelpful
comment about that.
Merlin Moncure, per an idea of Tom Lane's
These functions should take a pg_locale_t, not a collation OID, and should
call mbstowcs_l/wcstombs_l where available. Where those functions are not
available, temporarily select the correct locale with uselocale().
This change removes the bogus assumption that all locales selectable in
a given database have the same wide-character conversion method; in
particular, the collate.linux.utf8 regression test now passes with
LC_CTYPE=C, so long as the database encoding is UTF8.
I decided to move the char2wchar/wchar2char functions out of mbutils.c and
into pg_locale.c, because they work on wchar_t not pg_wchar_t and thus
don't really belong with the mbutils.c functions. Keeping them where they
were would have required importing pg_locale_t into pg_wchar.h somehow,
which did not seem like a good plan.
Since collation is effectively an argument, not a property of the function,
FmgrInfo is really the wrong place for it; and this becomes critical in
cases where a cached FmgrInfo is used for varying purposes that might need
different collation settings. Fix by passing it in FunctionCallInfoData
instead. In particular this allows a clean fix for bug #5970 (record_cmp
not working). This requires touching a bit more code than the original
method, but nobody ever thought that collations would not be an invasive
patch...
This involves getting the character classification and case-folding
functions in the regex library to use the collations infrastructure.
Most of this work had been done already in connection with the upper/lower
and LIKE logic, so it was a simple matter of transposition.
While at it, split out these functions into a separate source file
regc_pg_locale.c, so that they can be correctly labeled with the Postgres
project's license rather than the Scriptics license. These functions are
100% Postgres-written code whereas what remains in regc_locale.c is still
mostly not ours, so lumping them both under the same copyright notice was
getting more and more misleading.
ts_typanalyze.c computes MCE statistics as fractions of the non-null rows,
which seems fairly reasonable, and anyway changing it in released versions
wouldn't be a good idea. But then ts_selfuncs.c has to account for that.
Failure to do so results in overestimates in columns with a significant
fraction of null documents. Back-patch to 8.4 where this stuff was
introduced.
Jesper Krogh
This adds collation support for columns and domains, a COLLATE clause
to override it per expression, and B-tree index support.
Peter Eisentraut
reviewed by Pavel Stehule, Itagaki Takahiro, Robert Haas, Noah Misch
This patch eliminates per-chunk palloc overhead for most small allocations
needed in the representation of an ispell dictionary. This saves close to
a factor of 2 on the current Czech ispell data. While it doesn't cover
every last small allocation in the ispell code, we are at the point of
diminishing returns, because about 95% of the allocations are covered
already.
Pavel Stehule, rather heavily revised by Tom
Add explicit initialization and cleanup functions to spell.c, and keep
all working state in the already-existing ISpellDict struct. This lets us
get rid of a static variable along with some extremely shaky assumptions
about usage of child memory contexts.
This commit is just code beautification and has no impact on functionality
or performance, but it opens the way to a less-grotty implementation of
Pavel's memory-saving hack, which will follow shortly.
- Rename TSParserGetPrsid to get_ts_parser_oid.
- Rename TSDictionaryGetDictid to get_ts_dict_oid.
- Rename TSTemplateGetTmplid to get_ts_template_oid.
- Rename TSConfigGetCfgid to get_ts_config_oid.
- Rename FindConversionByName to get_conversion_oid.
- Rename GetConstraintName to get_constraint_oid.
- Add new functions get_opclass_oid, get_opfamily_oid, get_rewrite_oid,
get_rewrite_oid_without_relid, get_trigger_oid, and get_cast_oid.
The name of each function matches the corresponding catalog.
Thanks to KaiGai Kohei for the review.
bright, but it beats assuming that a prefix match behaves identically to an
exact match, which is what the code was doing before :-(. Noted while
experimenting with Artur Dobrowski's example.
possible (ie, whenever the tsquery is a constant), even when no statistics
are available for the tsvector. For example, foo @@ 'a & b'::tsquery
can be expected to be more selective than foo @@ 'a'::tsquery, whether
or not we know anything about foo. We use DEFAULT_TS_MATCH_SEL as the assumed
selectivity of individual query terms when no stats are available, then
combine the terms according to the query's AND/OR structure as usual.
Per experimentation with Artur Dabrowski's example. (The fact that there
are no stats available in that example is a problem in itself, but
nonetheless tsmatchsel should be smarter about the case.)
Back-patch to 8.4 to keep all versions of tsmatchsel() in sync.
We must filter out hashtable entries with frequencies less than those
specified by the algorithm, else we risk emitting junk entries whose
actual frequency is much less than other lexemes that did not get
tabulated. This is bad enough by itself, but even worse is that
tsquerysel() believes that the minimum frequency seen in pg_statistic is a
hard upper bound for lexemes not included, and was thus underestimating
the frequency of non-MCEs.
Also, set the threshold frequency to something with a little bit of theory
behind it, to wit assume that the input distribution is approximately
Zipfian. This might need adjustment in future, but some preliminary
experiments suggest that it's not too unreasonable.
Back-patch to 8.4, where this code was introduced.
Jan Urbanski, with some editorialization by Tom
My initial impression that glibc was measuring the precision in characters
(which is what the Linux man page says it does) was incorrect. It does take
the precision to be in bytes, but it also tries to truncate the string at a
character boundary. The bottom line remains the same: it will mess up
if the string is not in the encoding it expects, so we need to avoid %.*s
anytime there's a significant risk of that. Previous code changes are still
good, but adjust the comments to reflect this knowledge. Per research by
Hernan Gonzalez.
Depending on which spec you read, field widths and precisions in %s may be
counted either in bytes or characters. Our code was assuming bytes, which
is wrong at least for glibc's implementation, and in any case libc might
have a different idea of the prevailing encoding than we do. Hence, for
portable results we must avoid using anything more complex than just "%s"
unless the string to be printed is known to be all-ASCII.
This patch fixes the cases I could find, including the psql formatting
failure reported by Hernan Gonzalez. In HEAD only, I also added comments
to some places where it appears safe to continue using "%.*s".
to RFC 3986. In particular, these characters now terminate the path part
of a URL: '"', '<', '>', '\', '^', '`', '{', '|', '}'. The previous behavior
was inconsistent and depended on whether a "?" was present in the path.
Per gripe from Donald Fraser and spec research by Kevin Grittner.
This is a pre-existing bug, but not back-patching since the risks of
breaking existing applications seem to outweigh the benefits.
"column < constant", and the comparison value is in the first or last
histogram bin or outside the histogram entirely, try to fetch the actual
column min or max value using an index scan (if there is an index on the
column). If successful, replace the lower or upper histogram bound with
that value before carrying on with the estimate. This limits the
estimation error caused by moving min/max values when the comparison
value is close to the min or max. Per a complaint from Josh Berkus.
It is tempting to consider using this mechanism for mergejoinscansel as well,
but that would inject index fetches into main-line join estimation not just
endpoint cases. I'm refraining from that until we can get a better handle
on the costs of doing this type of lookup.
For long source strings the copying results in O(N^2) behavior, and the
multiplier can be significant if wide-char conversion is involved.
Andres Freund, reviewed by Kevin Grittner.
Heikki Linnakangas
Tom Lane
Bruce Momjian
Andrew Dunstan
Peter Eisentraut
Noah Misch
Robert Haas
Greg Stark
Teodor Sigaev
Magnus Hagander
Andres Freund
Stephen Frost
Alvaro Herrera