There are still some alignment-related failures in the buildfarm,
which might or might not be able to be fixed quickly, but I've also
just realized that it increased the size of many WAL records by 4 bytes
because a block reference contains a RelFileLocator. The effect of that
hasn't been studied or discussed, so revert for now.
RelFileNumbers are now assigned using a separate counter, instead of
being assigned from the OID counter. This counter never wraps around:
if all 2^56 possible RelFileNumbers are used, an internal error
occurs. As the cluster is limited to 2^64 total bytes of WAL, this
limitation should not cause a problem in practice.
If the counter were 64 bits wide rather than 56 bits wide, we would
need to increase the width of the BufferTag, which might adversely
impact buffer lookup performance. Also, this lets us use bigint for
pg_class.relfilenode and other places where these values are exposed
at the SQL level without worrying about overflow.
This should remove the need to keep "tombstone" files around until
the next checkpoint when relations are removed. We do that to keep
RelFileNumbers from being recycled, but now that won't happen
anyway. However, this patch doesn't actually change anything in
this area; it just makes it possible for a future patch to do so.
Dilip Kumar, based on an idea from Andres Freund, who also reviewed
some earlier versions of the patch. Further review and some
wordsmithing by me. Also reviewed at various points by Ashutosh
Sharma, Vignesh C, Amul Sul, Álvaro Herrera, and Tom Lane.
Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com
Previously, "GRANT foo TO bar" or "GRANT foo TO bar GRANTED BY baz"
would record the OID of the grantor in pg_auth_members.grantor, but
that role could later be dropped without modifying or removing the
pg_auth_members record. That's not great, because we typically try
to avoid dangling references in catalog data.
Now, a role grant depends on the grantor, and the grantor can't be
dropped without removing the grant or changing the grantor. "DROP
OWNED BY" will remove the grant, just as it does for other kinds of
privileges. "REASSIGN OWNED BY" will not, again just like what we do
in other cases involving privileges.
pg_auth_members now has an OID column, because that is needed in order
for dependencies to work. It also now has an index on the grantor
column, because otherwise dropping a role would require a sequential
scan of the entire table to see whether the role's OID is in use as
a grantor. That probably wouldn't be too large a problem in practice,
but it seems better to have an index just in case.
A follow-on patch is planned with the goal of more thoroughly
rationalizing the behavior of role grants. This patch is just trying
to do enough to make sure that the data we store in the catalogs is at
some basic level valid.
Patch by me, reviewed by Stephen Frost
Discussion: http://postgr.es/m/CA+TgmoaFr-RZeQ+WoQ5nKPv97oT9+aDgK_a5+qWHSgbDsMp1Vg@mail.gmail.com
We have been using the term RelFileNode to refer to either (1) the
integer that is used to name the sequence of files for a certain relation
within the directory set aside for that tablespace/database combination;
or (2) that value plus the OIDs of the tablespace and database; or
occasionally (3) the whole series of files created for a relation
based on those values. Using the same name for more than one thing is
confusing.
Replace RelFileNode with RelFileNumber when we're talking about just the
single number, i.e. (1) from above, and with RelFileLocator when we're
talking about all the things that are needed to locate a relation's files
on disk, i.e. (2) from above. In the places where we refer to (3) as
a relfilenode, instead refer to "relation storage".
Since there is a ton of SQL code in the world that knows about
pg_class.relfilenode, don't change the name of that column, or of other
SQL-facing things that derive their name from it.
On the other hand, do adjust closely-related internal terminology. For
example, the structure member names dbNode and spcNode appear to be
derived from the fact that the structure itself was called RelFileNode,
so change those to dbOid and spcOid. Likewise, various variables with
names like rnode and relnode get renamed appropriately, according to
how they're being used in context.
Hopefully, this is clearer than before. It is also preparation for
future patches that intend to widen the relfilenumber fields from its
current width of 32 bits. Variables that store a relfilenumber are now
declared as type RelFileNumber rather than type Oid; right now, these
are the same, but that can now more easily be changed.
Dilip Kumar, per an idea from me. Reviewed also by Andres Freund.
I fixed some whitespace issues, changed a couple of words in a
comment, and made one other minor correction.
Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com
Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com
Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
Commit aa0105141 assigned fixed OIDs to template0 and postgres
in a very ad-hoc way. Notably, instead of teaching Catalog.pm
about these OIDs, the unused_oids script was just hacked to
not show them as unused. That's problematic since, for example,
duplicate_oids wouldn't report any future conflict. Hence,
invent a macro DECLARE_OID_DEFINING_MACRO() that can be used to
define an OID that is known to Catalog.pm and will participate
in duplicate-detection as well as renumbering by renumber_oids.pl.
(We don't anticipate renumbering these particular OIDs, but we
might as well build out all the Catalog.pm infrastructure while
we're here.)
Another issue is that aa0105141 neglected to touch IsPinnedObject,
with the result that it now claimed template0 and postgres are
pinned. The right thing to do there seems to be to teach it that
no database is pinned, since in fact DROP DATABASE doesn't check
for pinned-ness (and at least for these cases, that is an
intentional choice). It's not clear whether this wrong answer
had any visible effect, but perhaps it could have resulted in
erroneous management of dependency entries.
In passing, rename the TemplateDbOid macro to Template1DbOid
to reduce confusion (likely we should have done that way back
when we invented template0, but we didn't), and rename the
OID macros for template0 and postgres to have a similar style.
There are no changes to postgres.bki here, so no need for a
catversion bump.
Discussion: https://postgr.es/m/2935358.1650479692@sss.pgh.pa.us
This patch allows "PGC_SUSET" parameters to be set by non-superusers
if they have been explicitly granted the privilege to do so.
The privilege to perform ALTER SYSTEM SET/RESET on a specific parameter
can also be granted.
Such privileges are cluster-wide, not per database. They are tracked
in a new shared catalog, pg_parameter_acl.
Granting and revoking these new privileges works as one would expect.
One caveat is that PGC_USERSET GUCs are unaffected by the SET privilege
--- one could wish that those were handled by a revocable grant to
PUBLIC, but they are not, because we couldn't make it robust enough
for GUCs defined by extensions.
Mark Dilger, reviewed at various times by Andrew Dunstan, Robert Haas,
Joshua Brindle, and myself
Discussion: https://postgr.es/m/3D691E20-C1D5-4B80-8BA5-6BEB63AF3029@enterprisedb.com
As of v14, pg_depend contains almost 7000 "pin" entries recording
the OIDs of built-in objects. This is a fair amount of bloat for
every database, and it adds time to pg_depend lookups as well as
initdb. We can get rid of all of those entries in favor of an OID
range check, i.e. "OIDs below FirstUnpinnedObjectId are pinned".
(template1 and the public schema are exceptions. Those exceptions
are now wired into IsPinnedObject() instead of initdb's code for
filling pg_depend, but it's the same amount of cruft either way.)
The contents of pg_shdepend are modified likewise.
Discussion: https://postgr.es/m/3737988.1618451008@sss.pgh.pa.us
GetNewOidWithIndex() generates a new OID one by one until it finds
one not in the relation. If there are very long runs of consecutive
existing OIDs, GetNewOidWithIndex() needs to iterate many times
in the loop to find unused OID. Since TOAST table can have a large
number of entries and there can be such long runs of OIDs, there is
the case where it takes so many iterations to find new OID not in
TOAST table. Furthermore if all (i.e., 2^32) OIDs are already used,
GetNewOidWithIndex() enters something like busy loop and repeats
the iterations until at least one OID is marked as unused.
There are some reported troubles caused by a large number of
iterations in GetNewOidWithIndex(). For example, when inserting
a billion of records into the table, all the backends doing that
insertion operation got hang with 100% CPU usage at some point.
Previously there was no easy way to detect that GetNewOidWithIndex()
failed to find unused OID many times. So, for example, gdb full
backtrace of hanged backends needed to be taken, in order to
investigate that trouble. This is inconvenient and may not be
available in some production environments.
To provide easy way for that, this commit makes GetNewOidWithIndex()
log that it iterates more than GETNEWOID_LOG_THRESHOLD but have
not yet found OID unused in the relation. Also this commit makes
it repeat logging with exponentially increasing intervals until
it iterates more than GETNEWOID_LOG_MAX_INTERVAL, and makes it
finally repeat logging every GETNEWOID_LOG_MAX_INTERVAL unless
an unused OID is found. Those macro variables are used not to
fill up the server log with the similar messages.
In the discusion at pgsql-hackers, there was another idea to report
the lots of iterations in GetNewOidWithIndex() via wait event.
But since GetNewOidWithIndex() traverses indexes to find unused
OID and which will do I/O, acquire locks, etc, which will overwrite
the wait event and reset it to nothing once done. So that idea
doesn't work well, and we didn't adopt it.
Author: Tomohiro Hiramitsu
Reviewed-by: Tatsuhito Kasahara, Kyotaro Horiguchi, Tom Lane, Fujii Masao
Discussion: https://postgr.es/m/16722-93043fb459a41073@postgresql.org
Move the system catalog index declarations from catalog/indexing.h to
the respective parent tables' catalog/pg_*.h files. The original
reason for having it split was that the old genbki system produced the
output in the order of the catalog files it read, so all the indexing
stuff needed to come separately. But this is no longer the case, and
keeping it together makes more sense.
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
Move the system catalog toast table declarations from
catalog/toasting.h to the respective parent tables' catalog/pg_*.h
files. The original reason for having it split was that the old
genbki system produced the output in the order of the catalog files it
read, so all the toasting stuff needed to come separately. But this
is no longer the case, and keeping it together makes more sense.
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
This patch creates a new extension property, "trusted". An extension
that's marked that way in its control file can be installed by a
non-superuser who has the CREATE privilege on the current database,
even if the extension contains objects that normally would have to be
created by a superuser. The objects within the extension will (by
default) be owned by the bootstrap superuser, but the extension itself
will be owned by the calling user. This allows replicating the old
behavior around trusted procedural languages, without all the
special-case logic in CREATE LANGUAGE. We have, however, chosen to
loosen the rules slightly: formerly, only a database owner could take
advantage of the special case that allowed installation of a trusted
language, but now anyone who has CREATE privilege can do so.
Having done that, we can delete the pg_pltemplate catalog, moving the
knowledge it contained into the extension script files for the various
PLs. This ends up being no change at all for the in-core PLs, but it is
a large step forward for external PLs: they can now have the same ease
of installation as core PLs do. The old "trusted PL" behavior was only
available to PLs that had entries in pg_pltemplate, but now any
extension can be marked trusted if appropriate.
This also removes one of the stumbling blocks for our Python 2 -> 3
migration, since the association of "plpythonu" with Python 2 is no
longer hard-wired into pg_pltemplate's initial contents. Exactly where
we go from here on that front remains to be settled, but one problem
is fixed.
Patch by me, reviewed by Peter Eisentraut, Stephen Frost, and others.
Discussion: https://postgr.es/m/5889.1566415762@sss.pgh.pa.us
This follows multiple complains from Peter Geoghegan, Andres Freund and
Alvaro Herrera that this issue ought to be dug more before actually
happening, if it happens.
Discussion: https://postgr.es/m/20191226144606.GA5659@alvherre.pgsql
The following renaming is done so as source files related to index
access methods are more consistent with table access methods (the
original names used for index AMs ware too generic, and could be
confused as including features related to table AMs):
- amapi.h -> indexam.h.
- amapi.c -> indexamapi.c. Here we have an equivalent with
backend/access/table/tableamapi.c.
- amvalidate.c -> indexamvalidate.c.
- amvalidate.h -> indexamvalidate.h.
- genam.c -> indexgenam.c.
- genam.h -> indexgenam.h.
This has been discussed during the development of v12 when table AM was
worked on, but the renaming never happened.
Author: Michael Paquier
Reviewed-by: Fabien Coelho, Julien Rouhaud
Discussion: https://postgr.es/m/20191223053434.GF34339@paquier.xyz
This is still using the 2.0 version of pg_bsd_indent.
I thought it would be good to commit this separately,
so as to document the differences between 2.0 and 2.1 behavior.
Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
The right way for IsCatalogRelation/Class to behave is to return true
for OIDs less than FirstBootstrapObjectId (not FirstNormalObjectId),
without any of the ad-hoc fooling around with schema membership.
The previous code was wrong because (1) it claimed that
information_schema tables were not catalog relations but their toast
tables were, which is silly; and (2) if you dropped and recreated
information_schema, which is a supported operation, the behavior
changed. That's even sillier. With this definition, "catalog
relations" are exactly the ones traceable to the postgres.bki data,
which seems like what we want.
With this simplification, we don't actually need access to the pg_class
tuple to identify a catalog relation; we only need its OID. Hence,
replace IsCatalogClass with "IsCatalogRelationOid(oid)". But keep
IsCatalogRelation as a convenience function.
This allows fixing some arguably-wrong semantics in contrib/sepgsql and
ReindexRelationConcurrently, which were using an IsSystemNamespace test
where what they really should be using is IsCatalogRelationOid. The
previous coding failed to protect toast tables of system catalogs, and
also was not on board with the general principle that user-created tables
do not become catalogs just by virtue of being renamed into pg_catalog.
We can also get rid of a messy hack in ReindexMultipleTables.
While we're at it, also rename IsSystemNamespace to IsCatalogNamespace,
because the previous name invited confusion with the more expansive
semantics used by IsSystemRelation/Class.
Also improve the comments in catalog.c.
There are a few remaining places in replication-related code that are
special-casing OIDs below FirstNormalObjectId. I'm inclined to think
those are wrong too, and if there should be any special case it should
just extend to FirstBootstrapObjectId. But first we need to debate
whether a FOR ALL TABLES publication should include information_schema.
Discussion: https://postgr.es/m/21697.1557092753@sss.pgh.pa.us
Discussion: https://postgr.es/m/15150.1557257111@sss.pgh.pa.us
Noticed while reviewing nearby code. Given all the disclaimers about
this not being meant as user-facing code, I wonder whether we should
make these non-translatable? But in any case there's little excuse
for them not to be good English.
The code in tqual.c is largely heap specific. Due to the upcoming
pluggable storage work, it therefore makes sense to move it into
access/heap/ (as the file's header notes, the tqual name isn't very
good).
But the various statically allocated snapshot and snapshot
initialization functions are now (see previous commit) generic and do
not depend on functions declared in tqual.h anymore. Therefore move.
Also move XidInMVCCSnapshot as that's useful for future AMs, and
already used outside of tqual.c.
Author: Andres Freund
Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
Most of these had been obsoleted by 568d4138c / the SnapshotNow
removal.
This is is preparation for moving most of tqual.[ch] into either
snapmgr.h or heapam.h, which in turn is in preparation for pluggable
table AMs.
Author: Andres Freund
Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
Previously tables declared WITH OIDS, including a significant fraction
of the catalog tables, stored the oid column not as a normal column,
but as part of the tuple header.
This special column was not shown by default, which was somewhat odd,
as it's often (consider e.g. pg_class.oid) one of the more important
parts of a row. Neither pg_dump nor COPY included the contents of the
oid column by default.
The fact that the oid column was not an ordinary column necessitated a
significant amount of special case code to support oid columns. That
already was painful for the existing, but upcoming work aiming to make
table storage pluggable, would have required expanding and duplicating
that "specialness" significantly.
WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0).
Remove it.
Removing includes:
- CREATE TABLE and ALTER TABLE syntax for declaring the table to be
WITH OIDS has been removed (WITH (oids[ = true]) will error out)
- pg_dump does not support dumping tables declared WITH OIDS and will
issue a warning when dumping one (and ignore the oid column).
- restoring an pg_dump archive with pg_restore will warn when
restoring a table with oid contents (and ignore the oid column)
- COPY will refuse to load binary dump that includes oids.
- pg_upgrade will error out when encountering tables declared WITH
OIDS, they have to be altered to remove the oid column first.
- Functionality to access the oid of the last inserted row (like
plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed.
The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false)
for CREATE TABLE) is still supported. While that requires a bit of
support code, it seems unnecessary to break applications / dumps that
do not use oids, and are explicit about not using them.
The biggest user of WITH OID columns was postgres' catalog. This
commit changes all 'magic' oid columns to be columns that are normally
declared and stored. To reduce unnecessary query breakage all the
newly added columns are still named 'oid', even if a table's column
naming scheme would indicate 'reloid' or such. This obviously
requires adapting a lot code, mostly replacing oid access via
HeapTupleGetOid() with access to the underlying Form_pg_*->oid column.
The bootstrap process now assigns oids for all oid columns in
genbki.pl that do not have an explicit value (starting at the largest
oid previously used), only oids assigned later by oids will be above
FirstBootstrapObjectId. As the oid column now is a normal column the
special bootstrap syntax for oids has been removed.
Oids are not automatically assigned during insertion anymore, all
backend code explicitly assigns oids with GetNewOidWithIndex(). For
the rare case that insertions into the catalog via SQL are called for
the new pg_nextoid() function can be used (which only works on catalog
tables).
The fact that oid columns on system tables are now normal columns
means that they will be included in the set of columns expanded
by * (i.e. SELECT * FROM pg_class will now include the table's oid,
previously it did not). It'd not technically be hard to hide oid
column by default, but that'd mean confusing behavior would either
have to be carried forward forever, or it'd cause breakage down the
line.
While it's not unlikely that further adjustments are needed, the
scope/invasiveness of the patch makes it worthwhile to get merge this
now. It's painful to maintain externally, too complicated to commit
after the code code freeze, and a dependency of a number of other
patches.
Catversion bump, for obvious reasons.
Author: Andres Freund, with contributions by John Naylor
Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
It has been project policy to create toast tables only for those catalogs
that might reasonably need one. Since this judgment call can change over
time, just create one for every catalog, as this can be useful when
creating rather-long entries in catalogs, with recent examples being in
the shape of policy expressions or customly-formatted SCRAM verifiers.
To prevent circular dependencies and to avoid adding complexity to VACUUM
FULL logic, exclude pg_class, pg_attribute, and pg_index. Also, to
prevent pg_upgrade from seeing a non-empty new cluster, exclude
pg_largeobject and pg_largeobject_metadata from the set as large object
data is handled as user data. Those relations have no reason to use a
toast table anyway.
Author: Joe Conway, John Naylor
Reviewed-by: Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/84ddff04-f122-784b-b6c5-3536804495f8@joeconway.com
When selecting a new OID, we take care to avoid picking one that's already
in use in the target table, so as not to create duplicates after the OID
counter has wrapped around. However, up to now we used SnapshotDirty when
scanning for pre-existing entries. That ignores committed-dead rows, so
that we could select an OID matching a deleted-but-not-yet-vacuumed row.
While that mostly worked, it has two problems:
* If recently deleted, the dead row might still be visible to MVCC
snapshots, creating a risk for duplicate OIDs when examining the catalogs
within our own transaction. Such duplication couldn't be visible outside
the object-creating transaction, though, and we've heard few if any field
reports corresponding to such a symptom.
* When selecting a TOAST OID, deleted toast rows definitely *are* visible
to SnapshotToast, and will remain so until vacuumed away. This leads to
a conflict that will manifest in errors like "unexpected chunk number 0
(expected 1) for toast value nnnnn". We've been seeing reports of such
errors from the field for years, but the cause was unclear before.
The fix is simple: just use SnapshotAny to search for conflicting rows.
This results in a slightly longer window before object OIDs can be
recycled, but that seems unlikely to create any large problems.
Pavan Deolasee
Discussion: https://postgr.es/m/CABOikdOgWT2hHkYG3Wwo2cyZJq2zfs1FH0FgX-=h4OLosXHf9w@mail.gmail.com
The file handling functions from fd.c were called with a diverse mix of
notations for the file permissions when they were opening new files.
Almost all files created by the server should have the same permissions
set. So change the API so that e.g. OpenTransientFile() automatically
uses the standard permissions set, and OpenTransientFilePerm() is a new
function that takes an explicit permissions set for the few cases where
it is needed. This also saves an unnecessary argument for call sites
that are just opening an existing file.
While we're reviewing these APIs, get rid of the FileName typedef and
use the standard const char * for the file name and mode_t for the file
mode. This makes these functions match other file handling functions
and removes an unnecessary layer of mysteriousness. We can also get rid
of a few casts that way.
Author: David Steele <david@pgmasters.net>
During pg_upgrade's restore run, all relfilenode choices should be
overridden by commands in the dump script. If we ever find ourselves
choosing a relfilenode in the ordinary way, someone blew it. Likewise for
pg_type OIDs. Since pg_upgrade might well succeed anyway, if there happens
not to be a conflict during the regression test run, we need assertions
here to keep us on the straight and narrow.
We might someday be able to remove the assertion in GetNewRelFileNode,
if pg_upgrade is rewritten to remove its assumption that old and new
relfilenodes always match. But it's hard to see how to get rid of the
pg_type OID constraint, since those OIDs are embedded in user tables
in some cases.
Back-patch as far as 9.5, because of the risk of back-patches breaking
something here even if it works in HEAD. I'd prefer to go back further,
but 9.4 fails both assertions due to get_rel_infos()'s use of a temporary
table. We can't use the later-branch solution of a CTE for compatibility
reasons (cf commit 5d16332e9), and it doesn't seem worth inventing some
other way to do the query. (I did check, by dint of changing the Asserts
to elog(WARNING), that there are no other cases of unwanted OID assignments
during 9.4's regression test run.)
Discussion: https://postgr.es/m/19785.1497215827@sss.pgh.pa.us
Transmit the leader's temp-namespace state to workers. This is important
because without it, the workers do not really have the same search path
as the leader. For example, there is no good reason (and no extant code
either) to prevent a worker from executing a temp function that the
leader created previously; but as things stood it would fail to find the
temp function, and then either fail or execute the wrong function entirely.
We still prohibit a worker from creating a temp namespace on its own.
In effect, a worker can only see the session's temp namespace if the leader
had created it before starting the worker, which seems like the right
semantics.
Also, transmit the leader's BackendId to workers, and arrange for workers
to use that when determining the physical file path of a temp relation
belonging to their session. While the original intent was to prevent such
accesses entirely, there were a number of holes in that, notably in places
like dbsize.c which assume they can safely access temp rels of other
sessions anyway. We might as well get this right, as a small down payment
on someday allowing workers to access the leader's temp tables. (With
this change, directly using "MyBackendId" as a relation or buffer backend
ID is deprecated; you should use BackendIdForTempRelations() instead.
I left a couple of such uses alone though, as they're not going to be
reachable in parallel workers until we do something about localbuf.c.)
Move the thou-shalt-not-access-thy-leader's-temp-tables prohibition down
into localbuf.c, which is where it actually matters, instead of having it
in relation_open(). This amounts to recognizing that access to temp
tables' catalog entries is perfectly safe in a worker, it's only the data
in local buffers that is problematic.
Having done all that, we can get rid of the test in has_parallel_hazard()
that says that use of a temp table's rowtype is unsafe in parallel workers.
That test was unduly expensive, and if we really did need such a
prohibition, that was not even close to being a bulletproof guard for it.
(For example, any user-defined function executed in a parallel worker
might have attempted such access.)
This will prevent users from creating roles which begin with "pg_" and
will check for those roles before allowing an upgrade using pg_upgrade.
This will allow for default roles to be provided at initdb time.
Reviews by José Luis Tallón and Robert Haas
Use "a" and "an" correctly, mostly in comments. Two error messages were
also fixed (they were just elogs, so no translation work required). Two
function comments in pg_proc.h were also fixed. Etsuro Fujita reported one
of these, but I found a lot more with grep.
Also fix a few other typos spotted while grepping for the a/an typos.
For example, "consists out of ..." -> "consists of ...". Plus a "though"/
"through" mixup reported by Euler Taveira.
Many of these typos were in old code, which would be nice to backpatch to
make future backpatching easier. But much of the code was new, and I didn't
feel like crafting separate patches for each branch. So no backpatching.
When implementing a replication solution ontop of logical decoding, two
related problems exist:
* How to safely keep track of replication progress
* How to change replication behavior, based on the origin of a row;
e.g. to avoid loops in bi-directional replication setups
The solution to these problems, as implemented here, consist out of
three parts:
1) 'replication origins', which identify nodes in a replication setup.
2) 'replication progress tracking', which remembers, for each
replication origin, how far replay has progressed in a efficient and
crash safe manner.
3) The ability to filter out changes performed on the behest of a
replication origin during logical decoding; this allows complex
replication topologies. E.g. by filtering all replayed changes out.
Most of this could also be implemented in "userspace", e.g. by inserting
additional rows contain origin information, but that ends up being much
less efficient and more complicated. We don't want to require various
replication solutions to reimplement logic for this independently. The
infrastructure is intended to be generic enough to be reusable.
This infrastructure also replaces the 'nodeid' infrastructure of commit
timestamps. It is intended to provide all the former capabilities,
except that there's only 2^16 different origins; but now they integrate
with logical decoding. Additionally more functionality is accessible via
SQL. Since the commit timestamp infrastructure has also been introduced
in 9.5 (commit 73c986add) changing the API is not a problem.
For now the number of origins for which the replication progress can be
tracked simultaneously is determined by the max_replication_slots
GUC. That GUC is not a perfect match to configure this, but there
doesn't seem to be sufficient reason to introduce a separate new one.
Bumps both catversion and wal page magic.
Author: Andres Freund, with contributions from Petr Jelinek and Craig Ringer
Reviewed-By: Heikki Linnakangas, Petr Jelinek, Robert Haas, Steve Singer
Discussion: 20150216002155.GI15326@awork2.anarazel.de,
20140923182422.GA15776@alap3.anarazel.de,
20131114172632.GE7522@alap2.anarazel.de
Commit a730183926 created rather a mess by
putting dependencies on backend-only include files into include/common.
We really shouldn't do that. To clean it up:
* Move TABLESPACE_VERSION_DIRECTORY back to its longtime home in
catalog/catalog.h. We won't consider this symbol part of the FE/BE API.
* Push enum ForkNumber from relfilenode.h into relpath.h. We'll consider
relpath.h as the source of truth for fork numbers, since relpath.c was
already partially serving that function, and anyway relfilenode.h was
kind of a random place for that enum.
* So, relfilenode.h now includes relpath.h rather than vice-versa. This
direction of dependency is fine. (That allows most, but not quite all,
of the existing explicit #includes of relpath.h to go away again.)
* Push forkname_to_number from catalog.c to relpath.c, just to centralize
fork number stuff a bit better.
* Push GetDatabasePath from catalog.c to relpath.c; it was rather odd
that the previous commit didn't keep this together with relpath().
* To avoid needing relfilenode.h in common/, redefine the underlying
function (now called GetRelationPath) as taking separate OID arguments,
and make the APIs using RelFileNode or RelFileNodeBackend into macro
wrappers. (The macros have a potential multiple-eval risk, but none of
the existing call sites have an issue with that; one of them had such a
risk already anyway.)
* Fix failure to follow the directions when "init" fork type was added;
specifically, the errhint in forkname_to_number wasn't updated, and neither
was the SGML documentation for pg_relation_size().
* Fix tablespace-path-too-long check in CreateTableSpace() to account for
fork-name component of maximum-length pathnames. This requires putting
FORKNAMECHARS into a header file, but it was rather useless (and
actually unreferenced) where it was.
The last couple of items are potentially back-patchable bug fixes,
if anyone is sufficiently excited about them; but personally I'm not.
Per a gripe from Christoph Berg about how include/common wasn't
self-contained.
Bruce Momjian
Robert Haas
Tom Lane
Peter Eisentraut
Fujii Masao
Michael Paquier
Amit Kapila
Andres Freund
Peter Eisentraut
Stephen Frost
Heikki Linnakangas