except that it returns the string 'NULL', rather than a SQL null, when called
with a null argument. This is often a much more useful behavior for
constructing dynamic queries. Add more discussion to the documentation
about how to use these functions.
Brendan Jurd
(if they'd be visible to the current user in pg_stat_activity).
This might look like it's subject to race conditions, but it's actually
pretty safe because at the time DeadLockReport() is constructing the
report, we haven't yet aborted our transaction and so we can expect that
everyone else involved in the deadlock is still blocked on some lock.
(There are corner cases where that might not be true, such as a statement
timeout triggering in another backend before we finish reporting; but at
worst we'd report a misleading activity string, so it seems acceptable
considering the usefulness of reporting the queries.)
Original patch by Itagaki Takahiro, heavily modified by me.
a new typedef TimeOffset to represent an intermediate time value. It's
either int64 or double as appropriate, and in most usages will be measured
in microseconds or seconds the same as Timestamp. We don't call it
Timestamp, though, since the value doesn't necessarily represent an absolute
time instant.
Warren Turkal
directly to all the member expressions, instead of the previous implementation
where the ARRAY[] constructor would infer a common element type and then we'd
coerce the finished array after the fact. This has a number of benefits,
one being that we can allow an empty ARRAY[] construct so long as its
element type is specified by such a cast.
Brendan Jurd, minor fixes by me.
dumps can be loaded into databases without the same tablespaces that the
source had. The option acts by suppressing all "SET default_tablespace"
commands, and also CREATE TABLESPACE commands in pg_dumpall's case.
Gavin Roy, with documentation and minor fixes by me.
ISO_8859-5 <-> MULE_INTERNAL conversion tables.
This was discovered when trying to convert a string containing those characters
from ISO_8859-5 to Windows-1251, because we use MULE_INTERNAL/KOI8R as an
intermediate encoding between those two.
While the missing "Yo" was just an omission in the conversion tables, there are
a few other characters like the "Numero" sign ("No" as a single character) that
exists in all the other cyrillic encodings (win1251, ISO_8859-5 and cp866), but
not in KOI8R. Added comments about that.
Patch by Sergey Burladyan. Back-patch to 7.4.
case where there is a match to the pattern overall but the user has specified
a parenthesized subexpression and that subexpression hasn't got a match.
An example is substring('foo' from 'foo(bar)?'). This should return NULL,
since (bar) isn't matched, but it was mistakenly returning the whole-pattern
match instead (ie, 'foo'). Per bug #4044 from Rui Martins.
This has been broken since the beginning; patch in all supported versions.
The old behavior was sufficiently inconsistent that it's impossible to believe
anyone is depending on it.
are declared to return set, and consist of just a single SELECT. We
can replace the FROM-item with a sub-SELECT and then optimize much as
if we were dealing with a view. Patch from Richard Rowell, cleaned up
by me.
errors in any commands, including in various clean targets that have so far
been handled inconsistently. make -i is available to ignore all errors in
a consistent and official way.
during a bitmap index scan. This cannot affect the query results
(since we're just dumping the TIDs into a bitmap) but it might offer
some advantage in locality of access to the index. Per Greg Stark.
value for a precision is negative, act as though precision weren't
specified at all, that is the whole .* part of the format spec should
be ignored. Our previous coding took it as .0 which is certainly
wrong. Per report from Kris Jurka and local testing.
Possibly this should be back-patched, but it would be good to get
some more testing first; in any case there are no known cases where
there's really a problem on the backend side.
support DTrace in the future.
Switch from using DTRACE_PROBEn macros to the dynamically generated macros.
Use "dtrace -h" to create a header file that contains the dynamically
generated macros to be used in the source code instead of the DTRACE_PROBEn
macros. A dummy header file is generated for builds without DTrace support.
Author: Robert Lor <Robert.Lor@sun.com>
oprofile shows that a nontrivial amount of time is being spent in
repeated calls to index_getprocinfo, which really only needs to be
called once. So do that, and inline _hash_datum2hashkey to make it
work.
linear search when checking child-transaction XIDs. This makes for an
important speedup in transactions that have large numbers of children,
as in a recent example from Craig Ringer. We can also get rid of an
ugly kluge that represented lists of TransactionIds as lists of OIDs.
Heikki Linnakangas
bucket number, so as to ensure locality of access to the index during the
insertion step. Without this, building an index significantly larger than
available RAM takes a very long time because of thrashing. On the other
hand, sorting is just useless overhead when the index does fit in RAM.
We choose to sort when the initial index size exceeds effective_cache_size.
This is a revised version of work by Tom Raney and Shreya Bhargava.
deals with the queue, including locking etc, is all in sinvaladt.c. This means
that the struct definition of the queue, and the queue pointer, are now
internal "implementation details" inside sinvaladt.c.
Per my proposal dated 25-Jun-2007 and followup discussion.
two buckets at the start, we create a number of buckets appropriate for the
estimated size of the table. This avoids a lot of expensive bucket-split
actions during initial index build on an already-populated table.
This is one of the two core ideas of Tom Raney and Shreya Bhargava's patch
to reduce hash index build time. I'm committing it separately to make it
easier for people to test the effects of this separately from the effects
of their other core idea (pre-sorting the index entries by bucket number).
This accidentally failed to fail before 8.3, because the context we were
switching back to was long-lived anyway; but it sure looks risky as can be
now. Well spotted by Pavan Deolasee.
job (i.e. to prevent Xid wraparound problems.) Bug reported by ITAGAKI
Takahiro in 20080314103837.63D3.52131E4D@oss.ntt.co.jp, though I didn't use his
patch.
that are reported as "equal" by wcscoll() are checked to see if they really
are bitwise equal, and are sorted per strcmp() if not. We made this happen
a couple of years ago in the regular code path, but it unaccountably got
left out of the Windows/UTF8 case (probably brain fade on my part at the
time). As in the prior set of changes, affected users may need to reindex
indexes on textual columns.
Backpatch as far as 8.2, which is the oldest release we are still supporting
on Windows.
messages if the calling transaction aborts later on. Collapsing out line
pointer redirects is a done deal as soon as we complete the page update,
so syscache *must* be notified even if the VACUUM FULL as a whole doesn't
complete. To fix, add some functionality to inval.c to allow the pending
inval messages to be sent immediately while heap_page_prune is still
running. The implementation is a bit chintzy: it will only work in the
context of VACUUM FULL. But that's all we need now, and it can always be
extended later if needed. Per my trouble report of a week ago.
(probably NULL) before exiting. Up to now it's just left the variable as it
set it, which means that after we're done processing the current client
message, ActiveSnapshot is probably pointing at garbage (because this function
is typically run in MessageContext which will get reset). There doesn't seem
to have been any code path in which that mattered before 8.3, but now the
plancache module might try to use the stale value if the next client message
is a Bind for a prepared statement that is in need of replanning. Per report
from Alex Hunsaker.
pg_listener modifications commanded by LISTEN and UNLISTEN until the end
of the current transaction. This allows us to hold the ExclusiveLock on
pg_listener until after commit, with no greater risk of deadlock than there
was before. Aside from fixing the race condition, this gets rid of a
truly ugly kludge that was there before, namely having to ignore
HeapTupleBeingUpdated failures during NOTIFY. There is a small potential
incompatibility, which is that if a transaction issues LISTEN or UNLISTEN
and then looks into pg_listener before committing, it won't see any resulting
row insertion or deletion, where before it would have. It seems unlikely
that anyone would be depending on that, though.
This patch also disallows LISTEN and UNLISTEN inside a prepared transaction.
That case had some pretty undesirable properties already, such as possibly
allowing pg_listener entries to be made for PIDs no longer present, so
disallowing it seems like a better idea than trying to maintain the behavior.
Tom Lane