document why this happens.  Remove exp() errno check because not needed.

having md.c return a success/failure boolean to smgr.c, which was just going
to elog anyway, let md.c issue the elog messages itself.  This allows better
error reporting, particularly in cases such as "short read" or "short write"
which Peter was complaining of.  Also, remove the kluge of allowing mdread()
to return zeroes from a read-beyond-EOF: this is now an error condition
except when InRecovery or zero_damaged_pages = true.  (Hash indexes used to
require that behavior, but no more.)  Also, enforce that mdwrite() is to be
used for rewriting existing blocks while mdextend() is to be used for
extending the relation EOF.  This restriction lets us get rid of the old
ad-hoc defense against creating huge files by an accidental reference to
a bogus block number: we'll only create new segments in mdextend() not
mdwrite() or mdread().  (Again, when InRecovery we allow it anyway, since
we need to allow updates of blocks that were later truncated away.)
Also, clean up the original makeshift patch for bug #2737: move the
responsibility for padding relation segments to full length into md.c.

only return Nan and set errno for pow/exp overflow/underflow.

platforms set errno, and we already have a check macro that detects
under/overflow, so there is no reason for platform-specific code
anymore.

with other places.

isinf(), fall through to our own infinity checks.

code path in tablecmds.c that wasn't exercised at all before.

infrastructure.

The purpose is to allow autovacuum-esq conditional vacuuming and
clustering using SQL to discover the required stats.

No documentation updates required.  Catalog version updated.

Glen Parker

valid result from a computation if one of the input values was infinity.
The previous code assumed an operation that returned infinity was an
overflow.

Handle underflow/overflow consistently, and add checks for aggregate
overflow.

Consistently prevent Inf/Nan from being cast to integer data types.

Fix INT_MIN % -1 to prevent overflow.

Update regression results for new error text.

Per report from Roman Kononov.

pg_opclass during LookupOpclassInfo(), I'd turned pg_opclass_oid_index
into a critical system index.  However the problem could only manifest
during a backend's first attempt to load opclass data, and then only
if it had successfully loaded pg_internal.init and subsequently received
a relcache flush; which made it impossible to reproduce in sequential
tests and darn hard even in parallel tests.  Memo to self: when
exercising cache flush scenarios, must disable LookupOpclassInfo's
internal cache too.

about typmod representation for standard types out into type-specific
typmod I/O functions.  Teodor Sigaev, with some editorialization by
Tom Lane.

Magnus Hagander

or contradictory keys even in cross-data-type scenarios.  This is another
benefit of the opfamily rewrite: we can find the needed comparison
operators now.

>   http://archives.postgresql.org/pgsql-hackers/2006-12/msg01213.php

< * Add a GUC to control whether BEGIN inside a transcation should abort
<   the transaction.

for use with constraint exclusion.  We can prove those cases now...

predicate operators.  The hard stuff turns out to be already done in the
previous commit, we need merely open the floodgates...

< * Move some /contrib modules out to their own project sites
<
<   Particularly, move GPL-licensed /contrib/userlock and
<   /contrib/dbmirror/clean_pending.pl.
<

the 8.1 SQL function definition for it.  Per report from Rajesh Kumar Mallah,
such a DBA error doesn't seem at all improbable, and the cost of checking for
it is not very high compared to the cost of running this function.  (It would
have been better to change the C name of the function so it wouldn't be called
by the old SQL definition, but it's too late for that now in the 8.2 branch.)

do this for ordinary SQL commands, so it seems consistent to do it for
backslash commands too.  Per gripe from Rajesh Kumar Mallah.

Per Thorkil Olesen.

multi-line comments to the next line.

of increasing size, instead of one at a time.  This reduces the memory
management overhead when num_temp_buffers is large: in the previous coding
we would actually waste 50% of the space used for temp buffers, because aset.c
would round the individual requests up to 16K.  Problem noted while studying
a performance issue reported by Steven Flatt.

Back-patch as far as 8.1 --- older versions used few enough local buffers
that the issue isn't significant for them.

has a small maxBlockSize: the maximum request size that we will treat as a
"chunk" needs to be limited to fit in maxBlockSize.  Otherwise we will round
up the request size to the next power of 2, wasting space, which is a bit
pointless if we aren't going to make the blocks big enough to fit additional
stuff in them.  The example motivating this is local buffer management, which
makes repeated allocations of 8K (one BLCKSZ buffer) in TopMemoryContext,
which has maxBlockSize = 8K because for the most part allocations there are
small.  This leads to each local buffer actually eating 16K of space, which
adds up when there are thousands of them.  I intend to change localbuf.c to
aggregate its requests, which will prevent this particular misbehavior, but
it seems likely that similar scenarios could arise elsewhere, so fixing the
core problem seems wise as well.

PQdsplen()) normally, instead of replacing them by \uXXXX sequences.
Assume that they in fact occupy zero screen space for formatting purposes.
Per gripe from Michael Fuhr and ensuing discussion.

remove long-obsolete statement that there isn't a check for infinite
recursion in view rules.

involving HashAggregate over SubqueryScan (this is the known case, there
may well be more).  The bug is only latent in releases before 8.2 since they
didn't try to access tupletable slots' descriptors during ExecDropTupleTable.
The least bogus fix seems to be to make subqueries share the parent query's
memory context, so that tupdescs they create will have the same lifespan as
those of the parent query.  There are comments in the code envisioning going
even further by not having a separate child EState at all, but that will
require rethinking executor access to range tables, which I don't want to
tackle right now.  Per bug report from Jean-Pierre Pelletier.