This first part of the background writer does no syncing at all.
It's only purpose is to keep the LRU heads clean so that regular
backends seldom to never have to call write().
Jan
pghackers proposal of 8-Nov. All the existing cross-type comparison
operators (int2/int4/int8 and float4/float8) have appropriate support.
The original proposal of storing the right-hand-side datatype as part of
the primary key for pg_amop and pg_amproc got modified a bit in the event;
it is easier to store zero as the 'default' case and only store a nonzero
when the operator is actually cross-type. Along the way, remove the
long-since-defunct bigbox_ops operator class.
Remove the 'strategy map' code, which was a large amount of mechanism
that no longer had any use except reverse-mapping from procedure OID to
strategy number. Passing the strategy number to the index AM in the
first place is simpler and faster.
This is a preliminary step in planned support for cross-datatype index
operations. I'm committing it now since the ScanKeyEntryInitialize()
API change touches quite a lot of files, and I want to commit those
changes before the tree drifts under me.
protocol, per report from Igor Shevchenko. NOTIFY thought it could
do its thing if transaction blockState is TBLOCK_DEFAULT, but in
reality it had better check the low-level transaction state is
TRANS_DEFAULT as well. Formerly it was not possible to wait for the
client in a state where the first is true and the second is not ...
but now we can have such a state. Minor cleanup in StartTransaction()
as well.
when the pg_class.relhassubclass value is already correct. This should
avoid most cases of the 'tuple concurrently updated' problem that
Robert Creager recently complained about. Also remove a bunch of dead
code in StoreCatalogInheritance() --- it was still computing the complete
list of direct and indirect inheritance ancestors, though that list has
not been needed since we got rid of the pg_ipl catalog.
a single LEFT JOIN query instead of firing the check trigger for each
row individually. Stephan Szabo, with some kibitzing from Tom Lane and
Jan Wieck.
before it is de-backslashed, not after. This allows the null string \N
to be reliably distinguished from the data value \N (which must be
represented as \\N). Per bug report from Manfred Koizar ... but it's
amazing this hasn't been reported before ...
Also, be consistent about encoding conversion for null string: the form
specified in the command is in the server encoding, but what is sent
to/from client must be in client encoding. This never worked quite
right before either.
to make them comparable to what UpdateStats does in the same situation.
I'm not certain two instances of vac_update_relstats could run in
parallel for the same relation, but parallel invocations of vac_update_dbstats
do seem possible.
discussion on pgsql-hackers: in READ COMMITTED mode we just have to force
a QuerySnapshot update in the trigger, but in SERIALIZABLE mode we have
to run the scan under a current snapshot and then complain if any rows
would be updated/deleted that are not visible in the transaction snapshot.
to allow es_snapshot to be set to SnapshotNow rather than a query snapshot.
This solves a bug reported by Wade Klaver, wherein triggers fired as a
result of RI cascade updates could misbehave.
now able to cope with assigning new relfilenode values to nailed-in-cache
indexes, so they can be reindexed using the fully crash-safe method. This
leaves only shared system indexes as special cases. Remove the 'index
deactivation' code, since it provides no useful protection in the shared-
index case. Require reindexing of shared indexes to be done in standalone
mode, but remove other restrictions on REINDEX. -P (IgnoreSystemIndexes)
now prevents using indexes for lookups, but does not disable index updates.
It is therefore safe to allow from PGOPTIONS. Upshot: reindexing system catalogs
can be done without a standalone backend for all cases except
shared catalogs.
Per recent discussion, this does not work because other backends can't
reliably see tuples in a temp table and so cannot run the RI checks
correctly. Seems better to disallow this case than go back to accessing
temp tables through shared buffers. Also, disallow FK references to
ON COMMIT DELETE ROWS tables. We already caught this problem for normal
TRUNCATE, but the path used by ON COMMIT didn't check.
reindexing system tables without ignoring system indexes, when the
other two varieties of REINDEX disallow it. Make all three act the same,
and simplify downstream code accordingly.
really general fix might be difficult, I believe the only case where
AtCommit_Notify could see an uncommitted tuple is where the other guy
has just unlistened and not yet committed. The best solution seems to
be to just skip updating that tuple, on the assumption that the other
guy does not want to hear about the notification anyway. This is not
perfect --- if the other guy rolls back his unlisten instead of committing,
then he really should have gotten this notify. But to do that, we'd have
to wait to see if he commits or not, or make UNLISTEN hold exclusive lock
on pg_listener until commit. Either of these answers is deadlock-prone,
not to mention horrible for interactive performance. Do it this way
for now. (What happened to that project to do LISTEN/NOTIFY in memory
with no table, anyway?)
datatype by array_eq and array_cmp; use this to solve problems with memory
leaks in array indexing support. The parser's equality_oper and ordering_oper
routines also use the cache. Change the operator search algorithms to look
for appropriate btree or hash index opclasses, instead of assuming operators
named '<' or '=' have the right semantics. (ORDER BY ASC/DESC now also look
at opclasses, instead of assuming '<' and '>' are the right things.) Add
several more index opclasses so that there is no regression in functionality
for base datatypes. initdb forced due to catalog additions.
via extended query protocol, because it sends Sync right after Execute
without realizing that the command to be executed is COPY. There seems
to be no reasonable way for it to realize that, either, so the best fix
seems to be to make the backend ignore Sync during copy-in mode. Bit of
a wart on the protocol, but little alternative. Also, libpq must send
another Sync after terminating the COPY, if the command was issued via
Execute.
yet, though). Avoid using nth() to fetch tlist entries; provide a
common routine get_tle_by_resno() to search a tlist for a particular
resno. This replaces a couple uses of nth() and a dozen hand-coded
search loops. Also, replace a few uses of nth(length-1, list) with
llast().
Jan Wieck
Tom Lane
Peter Eisentraut
Bruce Momjian
Hiroshi Inoue