renumbering of encoding IDs done between 8.2 and 8.3 turns out to break 8.2
initdb and psql if they are run with an 8.3beta1 libpq.so. For the moment
we can rearrange the order of enum pg_enc to keep the same number for
everything except PG_JOHAB, which isn't a problem since there are no direct
references to it in the 8.2 programs anyway. (This does force initdb
unfortunately.)
Going forward, we want to fix things so that encoding IDs can be changed
without an ABI break, and this commit includes the changes needed to allow
libpq's encoding IDs to be treated as fully independent of the backend's.
The main issue is that libpq clients should not include pg_wchar.h or
otherwise assume they know the specific values of libpq's encoding IDs,
since they might encounter version skew between pg_wchar.h and the libpq.so
they are using. To fix, have libpq officially export functions needed for
encoding name<=>ID conversion and validity checking; it was doing this
anyway unofficially.
It's still the case that we can't renumber backend encoding IDs until the
next bump in libpq's major version number, since doing so will break the
8.2-era client programs. However the code is now prepared to avoid this
type of problem in future.
Note that initdb is no longer a libpq client: we just pull in the two
source files we need directly. The patch also fixes a few places that
were being sloppy about checking for an unrecognized encoding name.
it affects. The original coding neglected tablespace entirely (causing
the indexes to move to the database's default tablespace) and for an index
belonging to a UNIQUE or PRIMARY KEY constraint, it would actually try to
assign the parent table's reloptions to the index :-(. Per bug #3672 and
subsequent investigation.
8.0 and 8.1 did not have reloptions, but the tablespace bug is present.
used to perform MIN(foo) or MAX(foo), since we want to discard null rows in
the indexscan anyway. (This would probably fall out for free if we were
injecting the IS NOT NULL clause somewhere earlier, but given the current
anatomy of the MIN/MAX optimization code we have to do it explicitly.
Fortunately, very little added code is needed.) Per a discussion with
Henk de Wit.
has been consumed, recheck against the latest value of RedoRecPtr before
really sending the signal. This avoids useless checkpoint activity if
XLogWrite is executed when we have a very stale local copy of RedoRecPtr.
The potential for useless checkpoint is very much worse in 8.3 because of
the walwriter process (which never does XLogInsert), so while this behavior
was intentional, it needs to be changed. Per report from Itagaki Takahiro.
on pg_global even to superusers, and replace it with checks in various
other places to complain about invalid uses of pg_global. This ends
up being a bit more code but it allows a more specific error message
to be given, and it un-breaks pg_tablespace_size() on pg_global.
Per discussion.
simplification gets detoasted before it is incorporated into a Const node.
Otherwise, if an immutable function were to return a TOAST pointer (an
unlikely case, but it can be made to happen), we would end up with a plan
that depends on the continued existence of the out-of-line toast datum.
a relation as a reason to invalidate a plan when the relation changes. This
handles scenarios such as dropping/recreating a sequence that is referenced by
nextval('seq') in a cached plan. Rather than teach plancache.c all about
digging through plan trees to find regclass Consts, we charge the planner's
setrefs.c with making a list of the relation OIDs on which each plan depends.
That way the list can be built cheaply during a plan tree traversal that has
to happen anyway. Per bug #3662 and subsequent discussion.
on CORE previously.
This module offers transaction ID's containing the original XID and the
transaction epoch as a bigint value to the user level. It also provides
a special txid_snapshot data type that contains an entire transactions
visibility snapshot information, which is useful to determine if a
particular txid was visible to a transaction or not.
The module has been tested by porting Slony-I from using its original
xxid data type.
Jan
as we do (and upstream Tcl doesn't). The loop limit might be subject
to negotiation if anyone ever tries to do regex debugging in Far
Eastern languages, but for now 1000 seems plenty. CHR_MAX was right out :-(
are converted to Postgres Assert() macros, instead of using <assert.h>
as formerly. No difference in production builds, but --enable-cassert
debug builds will get better coverage for regex testing.
