Var referencing the subselect output. While this case could possibly be made
to work, it seems not worth expending effort on. Per report from Magnus
Naeslund(f).
id (CVE-2006-0553). Also fix related bug in SET SESSION AUTHORIZATION that
allows unprivileged users to crash the server, if it has been compiled with
Asserts enabled. The escalation-of-privilege risk exists only in 8.1.0-8.1.2.
However, the Assert-crash risk exists in all releases back to 7.3.
Thanks to Akio Ishida for reporting this problem.
default"
> or "NO SCROLL is the default", it will be rejected as incorrect. The
> reason is that the default behavior is different from either of these,
> as is explained in the NOTES section.
Ok, so *that's* where the bit about the query plan being simple enough.
Based on that, ISTM that it should be premissable for us to decide that
a cursor requiring a sort isn't "simple enough" to support SCROLL.
In any case, here's a patch that makes the non-standard behavior easier
for people to find.
Jim C. Nasby
regardless of the current schema search path. Since CREATE OPERATOR CLASS
only allows one default opclass per datatype regardless of schemas, this
should have minimal impact, and it fixes problems with failure to find a
desired opclass while restoring dump files. Per discussion at
http://archives.postgresql.org/pgsql-hackers/2006-02/msg00284.php.
Remove now-redundant-or-unused code in typcache.c and namespace.c,
and backpatch as far as 8.0.
it later. This fixes a problem where EXEC_BACKEND didn't have progname
set, causing a segfault if log_min_messages was set below debug2 and our
own snprintf.c was being used.
Also alway strdup() progname.
Backpatch to 8.1.X and 8.0.X.
to avoid sharing substructure with the lower-level indexquals. This is
currently only an issue if there are SubPlans in the indexquals, which is
uncommon but not impossible --- see bug #2218 reported by Nicholas Vinen.
We use the same kluge for indexqual vs indexqualorig in the index scans
themselves ... would be nice to clean this up someday.
requested sort order. It was assuming that build_index_pathkeys always
generates a pathkey per index column, which was not true if implied equality
deduction had determined that two index columns were effectively equated to
each other. Simplest fix seems to be to install an option that causes
build_index_pathkeys to support this behavior as well as the original one.
Per report from Brian Hirt.
memory in the executor's per-query memory context. It also inefficient:
it invokes get_call_result_type() and TupleDescGetAttInMetadata() for
every call to return_next, rather than invoking them once (per PL/Perl
function call) and memoizing the result.
This patch makes the following changes:
- refactor the code to include all the "per PL/Perl function call" data
inside a single struct, "current_call_data". This means we don't need to
save and restore N pointers for every recursive call into PL/Perl, we
can just save and restore one.
- lookup the return type metadata needed by plperl_return_next() once,
and then stash it in "current_call_data", so as to avoid doing the
lookup for every call to return_next.
- create a temporary memory context in which to evaluate the return
type's input functions. This memory context is reset for each call to
return_next.
The patch appears to fix the memory leak, and substantially reduces
the overhead imposed by return_next.
While we normally prefer the notation "foo.*" for a whole-row Var, that does
not work at SELECT top level, because in that context the parser will assume
that what is wanted is to expand the "*" into a list of separate target
columns, yielding behavior different from a whole-row Var. We have to emit
just "foo" instead in that context. Per report from Sokolov Yura.
because pqSendSome will absorb input data anytime it'd be forced to block.
Avoiding a kernel call per PQputCopyData call helps COPY speed materially.
Alon Goldshuv
to try to create a log segment file concurrently, but the code erroneously
specified O_EXCL to open(), resulting in a needless failure. Before 7.4,
it was even a PANIC condition :-(. Correct code is actually simpler than
what we had, because we can just say O_CREAT to start with and not need a
second open() call. I believe this accounts for several recent reports of
hard-to-reproduce "could not create file ...: File exists" errors in both
pg_clog and pg_subtrans.
sizebitvec of tsearch2, as well as identical code in several other
contrib modules. This provided about a 20X speedup in building a
large tsearch2 index ... didn't try to measure its effects for other
operations. Thanks to Stephan Vollmer for providing a test case.
temp table not only our own process' tables. It's not real important
since vacuum.c will skip temp tables anyway, but might as well make the
code do what it claims to do.
index's support-function cache (in index_getprocinfo). Since none of that
data can change for an index that's in active use, it seems sufficient to
treat all open indexes the same way we were treating "nailed" system indexes
--- that is, just re-read the pg_class row and leave the rest of the relcache
entry strictly alone. The pg_class re-read might not be strictly necessary
either, but since the reltablespace and relfilenode can change in normal
operation it seems safest to do it. (We don't support changing any of the
other info about an index at all, at the moment.)
Back-patch as far as 8.0. It might be possible to adapt the patch to 7.4,
but it would take more work than I care to expend for such a low-probability
problem. 7.3 is out of luck for sure.
occurs when it tries to heap_open pg_tablespace. When control returns to
smgrcreate, that routine will be holding a dangling pointer to a closed
SMgrRelation, resulting in mayhem. This is of course a consequence of
the violation of proper module layering inherent in having smgr.c call
a tablespace command routine, but the simplest fix seems to be to change
the locking mechanism. There's no real need for TablespaceCreateDbspace
to touch pg_tablespace at all --- it's only opening it as a way of locking
against a parallel DROP TABLESPACE command. A much better answer is to
create a special-purpose LWLock to interlock these two operations.
This drops TablespaceCreateDbspace quite a few layers down the food chain
and makes it something reasonably safe for smgr to call.
This is utterly insignificant in normal operation, but it becomes a
problem during cache inval stress testing. The original coding in fact
had no leak --- the 8.0 List rewrite created the issue. I wonder whether
list_concat should pfree the discarded header?
files: avoid creating stats hashtable entries for tables that aren't being
touched except by vacuum/analyze, ensure that entries for dropped tables are
removed promptly, and tweak the data layout to avoid storing useless struct
padding. Also improve the performance of pgstat_vacuum_tabstat(), and make
sure that autovacuum invokes it exactly once per autovac cycle rather than
multiple times or not at all. This should cure recent complaints about 8.1
showing much higher stats I/O volume than was seen in 8.0. It'd still be a
good idea to revisit the design with an eye to not re-writing the entire
stats dataset every half second ... but that would be too much to backpatch,
I fear.
