to return NULL, instead of erroring out, if the target object is specified by
OID and we can't find that OID in the catalogs. Since these functions operate
internally on SnapshotNow rules, there is a race condition when using them
in user queries: the query's MVCC snapshot might "see" a catalog row that's
already committed dead, leading to a failure when the inquiry function is
applied. Returning NULL should generally provide more convenient behavior.
This issue has been complained of before, and in particular we are now seeing
it in the regression tests due to another recent patch.
to 10, to compensate for the recent change in default statistics target.
The original number was pulled out of the air anyway :-(, but it was picked
in the context of the old default, so holding the default size of the
MCELEM array constant seems the best thing. Per discussion.
pg_database_encoding_max_length() predicts the maximum character length
returned by wchar2char(). Per Hiroshi Inoue, MB_CUR_MAX isn't usable on
Windows because we allow encoding = UTF8 when the locale says differently;
and getting rid of it seems a good idea on general principles because it
narrows our dependence on libc's locale API just a little bit more.
Also install a check for overflow of the buffer size computation.
and certificate revokation list by using connection parameters or environment
variables.
Original patch by Mark Woodward, heavily reworked by Alvaro Herrera and
Magnus Hagander.
actual argument type of ANYARRAY to match an argument declared ANYARRAY,
so long as ANYELEMENT etc aren't used. I had overlooked the fact that this
is a possible case while fixing bug #3852; but it is possible because
pg_statistic contains columns declared ANYARRAY. Per gripe from Corey Horton.
when they are invoked by the parser. We had been setting up a snapshot at
plan time but really it needs to be done earlier, before parse analysis.
Per report from Dmitry Koterov.
Also fix two related problems discovered while poking at this one:
exec_bind_message called datatype input functions without establishing a
snapshot, and SET CONSTRAINTS IMMEDIATE could call trigger functions without
establishing a snapshot.
Backpatch to 8.2. The underlying problem goes much further back, but it is
masked in 8.1 and before because we didn't attempt to invoke domain check
constraints within datatype input. It would only be exposed if a C-language
datatype input function used the snapshot; which evidently none do, or we'd
have heard complaints sooner. Since this code has changed a lot over time,
a back-patch is hardly risk-free, and so I'm disinclined to patch further
than absolutely necessary.
vacuuming (it's not), say "database-wide VACUUM" instead of "full-database
VACUUM" in the relevant hint messages. Also, document the permissions needed
to do this. Per today's discussion.
right child if it doesn't need to. This saves some miniscule number
of cycles, but the ulterior motive is to avoid an optimization bug
known to exist in SCO's C compiler (and perhaps others?)
replication patch needs a signal, but we've already used SIGUSR1 and
SIGUSR2 in normal backends. This patch allows reusing SIGUSR1 for that,
and for other purposes too if the need arises.
where no function stats entries exist. Partial response to Pavel's
observation that small VACUUM operations are noticeably slower in CVS HEAD
than 8.3.
form a join and that case doesn't have anything to join to. (We could
probably make it work if we didn't pull up the subquery, but it seems to
me that the case isn't worth extra code.) Per report from Greg Stark.
appendix on key words. catdesc was originally intended as computer-readable,
but since we ended up adding catcode, we can have more elaborate descriptions.
non-writable large objects need to have their snapshots registered on the
transaction resowner, not the current portal's, because it must persist until
the large object is closed (which the portal does not). Also, ensure that the
serializable snapshot is recorded by the transaction resource owner too, even
when a subtransaction has changed the current resource owner before
serializable is taken.
Per bug reports from Pavan Deolasee.
the visibility map patch that because autovacuum always sets
VacuumStmt->freeze_min_age, visibility map was never used for autovacuum,
only for manually launched vacuums. This patch introduces a new scan_all
field to VacuumStmt, indicating explicitly whether the visibility map
should be used, or the whole relation should be scanned, to advance
relfrozenxid. Anti-wraparound vacuums still need to scan all pages.
it's connection. This is required for applications that unload
the libpq library (such as PHP) in which case we'd otherwise
have pointers to these functions when they no longer exist.
This needs a bit more testing before we can consider a backpatch,
so not doing that yet.
In passing, remove unused functions in backend/libpq.
Bruce Momjian and Magnus Hagander, per report and analysis
by Russell Smith.
heap page, where a set bit indicates that all tuples on the page are
visible to all transactions, and the page therefore doesn't need
vacuuming. It is stored in a new relation fork.
Lazy vacuum uses the visibility map to skip pages that don't need
vacuuming. Vacuum is also responsible for setting the bits in the map.
In the future, this can hopefully be used to implement index-only-scans,
but we can't currently guarantee that the visibility map is always 100%
up-to-date.
In addition to the visibility map, there's a new PD_ALL_VISIBLE flag on
each heap page, also indicating that all tuples on the page are visible to
all transactions. It's important that this flag is kept up-to-date. It
is also used to skip visibility tests in sequential scans, which gives a
small performance gain on seqscans.
