Add context info to OAT_POST_CREATE security hook

... and have sepgsql use it to determine whether to check permissions
during certain operations.  Indexes that are being created as a result
of REINDEX, for instance, do not need to have their permissions checked;
they were already checked when the index was created.

Author: KaiGai Kohei, slightly revised by me
When converting a table to a view, remove its system columns.

Views should not have any pg_attribute entries for system columns.
However, we forgot to remove such entries when converting a table to a
view.  This could lead to crashes later on, if someone attempted to
reference such a column, as reported by Kohei KaiGai.

Patch in HEAD only.  This bug has been there forever, but in the back
branches we will have to defend against existing mis-converted views,
so it doesn't seem worthwhile to change the conversion code too.
Tweak genericcostestimate's fudge factor for index size.

To provide some bias against using a large index when a small one would do
as well, genericcostestimate adds a "fudge factor", which for a long time
was random_page_cost * index_pages/10000.  However, this can grow to be the
dominant term in indexscan cost estimates when the index involved is large
enough, a behavior that was never intended.  Change to a ln(1 + n/10000)
formulation, which has nearly the same behavior up to a few hundred pages
but tails off significantly thereafter.  (A log curve seems correct on
first principles, since what we're trying to account for here is index
descent costs, which are typically logarithmic.)  Per bug #7619 from Niko
Kiirala.

Possibly this change should get back-patched, but I'm hesitant to mess with
cost estimates in stable branches.
In pg_dump, dump SEQUENCE SET items in the data not pre-data section.

Represent a sequence's current value as a separate TableDataInfo dumpable
object, so that it can be dumped within the data section of the archive
rather than in pre-data.  This fixes an undesirable inconsistency between
the meanings of "--data-only" and "--section=data", and also fixes dumping
of sequences that are marked as extension configuration tables, as per a
report from Marko Kreen back in July.  The main cost is that we do one more
SQL query per sequence, but that's probably not very meaningful in most
databases.

Back-patch to 9.1, since it has the extension configuration issue even
though not the --section switch.
Prefer actual constants to pseudo-constants in equivalence class machinery.

generate_base_implied_equalities_const() should prefer plain Consts over
other em_is_const eclass members when choosing the "pivot" value that
all the other members will be equated to.  This makes it more likely that
the generated equalities will be useful in constraint-exclusion proofs.
Per report from Rushabh Lathia.
Throw error if expiring tuple is again updated or deleted.

This prevents surprising behavior when a FOR EACH ROW trigger
BEFORE UPDATE or BEFORE DELETE directly or indirectly updates or
deletes the the old row.  Prior to this patch the requested action
on the row could be silently ignored while all triggered actions
based on the occurence of the requested action could be committed.
One example of how this could happen is if the BEFORE DELETE
trigger for a "parent" row deleted "children" which had trigger
functions to update summary or status data on the parent.

This also prevents similar surprising problems if the query has a
volatile function which updates a target row while it is already
being updated.

There are related issues present in FOR UPDATE cursors and READ
COMMITTED queries which are not handled by this patch.  These
issues need further evalution to determine what change, if any, is
needed.

Where the new error messages are generated, in most cases the best
fix will be to move code from the BEFORE trigger to an AFTER
trigger.  Where this is not feasible, the trigger can avoid the
error by re-issuing the triggering statement and returning NULL.

Documentation changes will be submitted in a separate patch.

Kevin Grittner and Tom Lane with input from Florian Pflug and
Robert Haas, based on problems encountered during conversion of
Wisconsin Circuit Court trigger logic to plpgsql triggers.
Preserve intermediate .c files in coverage mode

The introduction of the .y -> .c pattern rule causes some .c files such
as bootparse.c to be considered intermediate files in the .y -> .c -> .o
rule chain, which make would automatically delete.  But in coverage
mode, the processing tools such as genhtml need those files, so mark
them as "precious" so that make preserves them.
Fix ALTER EXTENSION / SET SCHEMA

In its original conception, it was leaving some objects into the old
schema, but without their proper pg_depend entries; this meant that the
old schema could be dropped, causing future pg_dump calls to fail on the
affected database.  This was originally reported by Jeff Frost as #6704;
there have been other complaints elsewhere that can probably be traced
to this bug.

To fix, be more consistent about altering a table's subsidiary objects
along the table itself; this requires some restructuring in how tables
are relocated when altering an extension -- hence the new
AlterTableNamespaceInternal routine which encapsulates it for both the
ALTER TABLE and the ALTER EXTENSION cases.

There was another bug lurking here, which was unmasked after fixing the
previous one: certain objects would be reached twice via the dependency
graph, and the second attempt to move them would cause the entire
operation to fail.  Per discussion, it seems the best fix for this is to
do more careful tracking of objects already moved: we now maintain a
list of moved objects, to avoid attempting to do it twice for the same
object.

Authors: Alvaro Herrera, Dimitri Fontaine
Reviewed by Tom Lane
Fix erroneous choices of segNo variables

Commit dfda6eba (which changed segment numbers to use a single 64 bit
variable instead of log/seg) introduced a couple of bogus choices of
exactly which log segment number variable to use in each case.

This is currently pretty harmless; in one place, the bogus number was
only being used in an error message for a pretty unlikely condition
(failure to fsync a WAL segment file).  In the other, it was using a
global variable instead of the local variable; but all callsites were
passing the value of the global variable anyway.

No need to backpatch because that commit is not on earlier branches.
Document that TCP keepalive settings read as 0 on Unix-socket connections.

Per bug #7631 from Rob Johnson.  The code is operating as designed, but the
docs didn't explain it.
Fix erroneous choice of timeline variable, too
Have make never delete intermediate files automatically

Several hacks in certain modes already thought this was a bad idea, so
just disable it globally.
Limit the number of rel sets considered in consider_index_join_outer_rels.

In bug #7626, Brian Dunavant exposes a performance problem created by
commit 3b8968f25232ad09001bf35ab4cc59f5a501193e: that commit attempted to
consider *all* possible combinations of indexable join clauses, but if said
clauses join to enough different relations, there's an exponential increase
in the number of outer-relation sets considered.

In Brian's example, all the clauses come from the same equivalence class,
which means it's redundant to use more than one of them in an indexscan
anyway.  So we can prevent the problem in this class of cases (which is
probably the majority of real examples) by rejecting combinations that
would only serve to add a known-redundant clause.

But that still leaves us exposed to exponential growth of planning time
when the query has a lot of non-equivalence join clauses that are usable
with the same index.  I chose to prevent such cases by setting an upper
limit on the number of relation sets considered, equal to ten times the
number of index clauses considered so far.  (This sliding limit still
allows new relsets to be added on as we move to additional index columns,
which is probably more important than considering even more combinations of
clauses for the previous column.)  This should keep the amount of work done
roughly linear rather than exponential in the apparent query complexity.
This part of the fix is pretty ad-hoc; but without a clearer idea of
real-world cases for which this would result in markedly inferior plans,
it's hard to see how to do better.
Fix bogus handling of $(X) (i.e., ".exe") in isolationtester Makefile.

I'm not sure why commit 1eb1dde049ccfffc42c80c2bcec14155c58bcc1f seems
to have made this start to fail on Cygwin when it never did before ---
but nonetheless, the coding was pretty bogus, and unlike the way we
handle $(X) anywhere else.  Per buildfarm.
Fix typo
Fix handling of inherited check constraints in ALTER COLUMN TYPE.

This case got broken in 8.4 by the addition of an error check that
complains if ALTER TABLE ONLY is used on a table that has children.
We do use ONLY for this situation, but it's okay because the necessary
recursion occurs at a higher level.  So we need to have a separate
flag to suppress recursion without making the error check.

Reported and patched by Pavan Deolasee, with some editorial adjustments by
me.  Back-patch to 8.4, since this is a regression of functionality that
worked in earlier branches.
In pg_upgrade, set synchronous_commit=off for the new cluster, to
improve performance when restoring the schema from the old cluster.

Backpatch to 9.2.
Make the streaming replication protocol messages architecture-independent.

We used to send structs wrapped in CopyData messages, which works as long as
the client and server agree on things like endianess, timestamp format and
alignment. That's good enough for running a standby server, which has to run
on the same platform anyway, but it's useful for tools like pg_receivexlog
to work across platforms.

This breaks protocol compatibility of streaming replication, but we never
promised that to be compatible across versions, anyway.
In pg_upgrade docs, mention using base backup as part of rsync for
logical replication upgrades.

Backpatch to 9.2.
Don't try to use a unopened relation

Commit 4c9d0901 mistakenly introduced a call to
TransferPredicateLocksToHeapRelation() on an index relation that had
been closed a few lines above.  Moving up an index_open() call that's
below is enough to fix the problem.

Discovered by me while testing an unrelated patch.