We now create contype='n' pg_constraint rows for not-null constraints on
user tables. Only one such constraint is allowed for a column.
We propagate these constraints to other tables during operations such as
adding inheritance relationships, creating and attaching partitions and
creating tables LIKE other tables. These related constraints mostly
follow the well-known rules of conislocal and coninhcount that we have
for CHECK constraints, with some adaptations: for example, as opposed to
CHECK constraints, we don't match not-null ones by name when descending
a hierarchy to alter or remove it, instead matching by the name of the
column that they apply to. This means we don't require the constraint
names to be identical across a hierarchy.
The inheritance status of these constraints can be controlled: now we
can be sure that if a parent table has one, then all children will have
it as well. They can optionally be marked NO INHERIT, and then children
are free not to have one. (There's currently no support for altering a
NO INHERIT constraint into inheriting down the hierarchy, but that's a
desirable future feature.)
This also opens the door for having these constraints be marked NOT
VALID, as well as allowing UNIQUE+NOT NULL to be used for functional
dependency determination, as envisioned by commit e49ae8d3bc. It's
likely possible to allow DEFERRABLE constraints as followup work, as
well.
psql shows these constraints in \d+, though we may want to reconsider if
this turns out to be too noisy. Earlier versions of this patch hid
constraints that were on the same columns of the primary key, but I'm
not sure that that's very useful. If clutter is a problem, we might be
better off inventing a new \d++ command and not showing the constraints
in \d+.
For now, we omit these constraints on system catalog columns, because
they're unlikely to achieve anything.
The main difference to the previous attempt at this (b0e96f3119) is
that we now require that such a constraint always exists when a primary
key is in the column; we didn't require this previously which had a
number of unpalatable consequences. With this requirement, the code is
easier to reason about. For example:
- We no longer have "throwaway constraints" during pg_dump. We needed
those for the case where a table had a PK without a not-null
underneath, to prevent a slow scan of the data during restore of the
PK creation, which was particularly problematic for pg_upgrade.
- We no longer have to cope with attnotnull being set spuriously in
case a primary key is dropped indirectly (e.g., via DROP COLUMN).
Some bits of code in this patch were authored by Jian He.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Bernd Helmle <mailings@oopsware.de>
Reviewed-by: 何建 (jian he) <jian.universality@gmail.com>
Reviewed-by: 王刚 (Tender Wang) <tndrwang@gmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/202408310358.sdhumtyuy2ht@alvherre.pgsql
There are some problems with the new way to handle these constraints
that were detected at the last minute, and require fixes that appear too
invasive to be doing this late in the cycle. Revert this (again) for
now, we'll try again with these problems fixed.
The following commits are reverted:
b0e96f3119 Catalog not-null constraints
9b581c5341 Disallow changing NO INHERIT status of a not-null constraint
d0ec2ddbe0 Fix not-null constraint test
ac22a9545c Move privilege check to the right place
b0f7dd915b Check stack depth in new recursive functions
3af7217942 Update information_schema definition for not-null constraints
c3709100be Fix propagating attnotnull in multiple inheritance
d9f686a72e Fix restore of not-null constraints with inheritance
d72d32f52d Don't try to assign smart names to constraints
0cd711271d Better handle indirect constraint drops
13daa33fa5 Disallow NO INHERIT not-null constraints on partitioned tables
d45597f72f Disallow direct change of NO INHERIT of not-null constraints
21ac38f498 Fix inconsistencies in error messages
Discussion: https://postgr.es/m/202405110940.joxlqcx4dogd@alvherre.pgsql
We now create contype='n' pg_constraint rows for not-null constraints.
We propagate these constraints to other tables during operations such as
adding inheritance relationships, creating and attaching partitions and
creating tables LIKE other tables. We also spawn not-null constraints
for inheritance child tables when their parents have primary keys.
These related constraints mostly follow the well-known rules of
conislocal and coninhcount that we have for CHECK constraints, with some
adaptations: for example, as opposed to CHECK constraints, we don't
match not-null ones by name when descending a hierarchy to alter it,
instead matching by column name that they apply to. This means we don't
require the constraint names to be identical across a hierarchy.
For now, we omit them for system catalogs. Maybe this is worth
reconsidering. We don't support NOT VALID nor DEFERRABLE clauses
either; these can be added as separate features later (this patch is
already large and complicated enough.)
psql shows these constraints in \d+.
pg_dump requires some ad-hoc hacks, particularly when dumping a primary
key. We now create one "throwaway" not-null constraint for each column
in the PK together with the CREATE TABLE command, and once the PK is
created, all those throwaway constraints are removed. This avoids
having to check each tuple for nullness when the dump restores the
primary key creation.
pg_upgrading from an older release requires a somewhat brittle procedure
to create a constraint state that matches what would be created if the
database were being created fresh in Postgres 17. I have tested all the
scenarios I could think of, and it works correctly as far as I can tell,
but I could have neglected weird cases.
This patch has been very long in the making. The first patch was
written by Bernd Helmle in 2010 to add a new pg_constraint.contype value
('n'), which I (Álvaro) then hijacked in 2011 and 2012, until that one
was killed by the realization that we ought to use contype='c' instead:
manufactured CHECK constraints. However, later SQL standard
development, as well as nonobvious emergent properties of that design
(mostly, failure to distinguish them from "normal" CHECK constraints as
well as the performance implication of having to test the CHECK
expression) led us to reconsider this choice, so now the current
implementation uses contype='n' again. During Postgres 16 this had
already been introduced by commit e056c557ae, but there were some
problems mainly with the pg_upgrade procedure that couldn't be fixed in
reasonable time, so it was reverted.
In 2016 Vitaly Burovoy also worked on this feature[1] but found no
consensus for his proposed approach, which was claimed to be closer to
the letter of the standard, requiring an additional pg_attribute column
to track the OID of the not-null constraint for that column.
[1] https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Bernd Helmle <mailings@oopsware.de>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
CREATE TABLE AS has been preferred over SELECT INTO (outside of ecpg
and PL/pgSQL) for a long time. There were still a few uses of SELECT
INTO in tests and documentation, some old, some more recent. This
changes them to CREATE TABLE AS. Some occurrences in the tests remain
where they are specifically testing SELECT INTO parsing or similar.
Discussion: https://www.postgresql.org/message-id/flat/96dc0df3-e13a-a85d-d045-d6e2c85218da%40enterprisedb.com
Commit 0a2bc5d61e changed the order that permissions on the final and
transition functions of an aggregate are checked in. That shows up as a
difference in the order the LOG messages in this sepgsql regression test
are printed. Adjust the expected output.
Per buildfarm failure in rhinoceros.
fixup_whole_row_references() did the wrong thing with a dropped column,
resulting in a commit-time warning about a cache reference leak.
I (tgl) added a test case exercising this, but back-patched the test
only as far as v10; the patch didn't apply cleanly to 9.6 and it
didn't seem worth the trouble to adapt it. The bug is pretty old
though, so apply the code change all the way back.
Michael Luo, with cosmetic improvements by me
Discussion: https://postgr.es/m/BYAPR08MB5606D1453D7F50E2AF4D2FD29AD80@BYAPR08MB5606.namprd08.prod.outlook.com
Use SELinux "db_table: { truncate }" to check if permission is granted to
TRUNCATE. Update example SELinux policy to grant needed permission for
TRUNCATE. Add new regression test to demonstrate a positive and negative
cases. Test will only be run if the loaded SELinux policy has the
"db_table: { truncate }" permission. Makes use of recent commit which added
object TRUNCATE hook. Patch by Yuli Khodorkovskiy with minor
editorialization by me. Not back-patched because the object TRUNCATE hook
was not.
Author: Yuli Khodorkovskiy
Reviewed-by: Joe Conway
Discussion: https://postgr.es/m/CAFL5wJcomybj1Xdw7qWmPJRpGuFukKgNrDb6uVBaCMgYS9dkaA%40mail.gmail.com
1df5875 has changed the way dependencies are dropped for this command
with inheritance trees, which impacts sepgsql. This just updates the
regression test output to take care of the failures and adapt to the new
code.
Reported by buildfarm member rhinoceros.
Author: Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20191013101331.GC1434@paquier.xyz
Backpatch-through: 12
The aggregate-order difference explained in my previous commit
turns out to also affect the order of log entries emitted in the
contrib/sepgsql regression test. Per buildfarm.
Discussion: https://postgr.es/m/21272.1563318411@sss.pgh.pa.us
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
Commit bf6c614a2f broke the sepgsql test
due to a new invocation of the function access hook during grouping
equal initialization.
The new behaviour seems at least as correct as the old one, so try
adapt the tests. As I've no working sepgsql setup here, this is just
going from buildfarm results.
Author: Andres Freund
Discussion: https://postgr.es/m/20180217000337.lfsdvro3l6ccsksp@alap3.anarazel.de
Commit 15ce775 changed tuple-routing constraint checking logic.
This affects the expected output for contrib/sepgsql, because
there's no longer LOG entries reporting allowance of int4eq()
execution. Per buildfarm.
Commit 3ec76ff1f changed the partitioning logic to not install a forced
NOT NULL constraint on range partitioning columns. This affects the
expected output for contrib/sepgsql, because there's no longer LOG
entries reporting allowance of such a constraint. Per buildfarm.
The new partitioned table capability added a new relkind, namely
RELKIND_PARTITIONED_TABLE. Update sepgsql to treat this new relkind
exactly the same way it does RELKIND_RELATION.
In addition, add regression test coverage for partitioned tables.
Issue raised by Stephen Frost and initial patch by Mike Palmiotto.
Review by Tom Lane and Robert Haas, and editorializing by me.
Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
To ensure that "make installcheck" can be used safely against an existing
installation, we need to be careful about what global object names
(database, role, and tablespace names) we use; otherwise we might
accidentally clobber important objects. There's been a weak consensus that
test databases should have names including "regression", and that test role
names should start with "regress_", but we didn't have any particular rule
about tablespace names; and neither of the other rules was followed with
any consistency either.
This commit moves us a long way towards having a hard-and-fast rule that
regression test databases must have names including "regression", and that
test role and tablespace names must start with "regress_". It's not
completely there because I did not touch some test cases in rolenames.sql
that test creation of special role names like "session_user". That will
require some rethinking of exactly what we want to test, whereas the intent
of this patch is just to hit all the cases in which the needed renamings
are cosmetic.
There is no enforcement mechanism in this patch either, but if we don't
add one we can expect that the tests will soon be violating the convention
again. Again, that's not such a cosmetic change and it will require
discussion. (But I did use a quick-hack enforcement patch to find these
cases.)
Discussion: <16638.1468620817@sss.pgh.pa.us>
Recent commit 0426f349e changed handling of error context reports
in such a way to have a minor effect on the sepgsql regression
output. Adapt the expected output file to suit. Since that commit
was HEAD only, so is this one.
Remove the code in plpgsql that suppressed the innermost line of CONTEXT
for messages emitted by RAISE commands. That was never more than a quick
backwards-compatibility hack, and it's pretty silly in cases where the
RAISE is nested in several levels of function. What's more, it violated
our design theory that verbosity of error reports should be controlled
on the client side not the server side.
To alleviate the resulting noise increase, introduce a feature in libpq
and psql whereby the CONTEXT field of messages can be suppressed, either
always or only for non-error messages. Printing CONTEXT for errors only
is now their default behavior.
The actual code changes here are pretty small, but the effects on the
regression test outputs are widespread. I had to edit some of the
alternative expected outputs by hand; hopefully the buildfarm will soon
find anything I fat-fingered.
In passing, fix up (again) the output line counts in psql's various
help displays. Add some commentary about how to verify them.
Pavel Stehule, reviewed by Petr Jelínek, Jeevan Chalke, and others
The regression tests for sepgsql were broken by changes in the
base distro as-shipped policies. Specifically, definition of
unconfined_t in the system default policy was changed to bypass
multi-category rules, which the regression test depended on.
Fix that by defining a custom privileged domain
(sepgsql_regtest_superuser_t) and using it instead of system's
unconfined_t domain. The new sepgsql_regtest_superuser_t domain
performs almost like the current unconfined_t, but restricted by
multi-category policy as the traditional unconfined_t was.
The custom policy module is a self defined domain, and so should not
be affected by related future system policy changes. However, it still
uses the unconfined_u:unconfined_r pair for selinux-user and role.
Those definitions have not been changed for several years and seem
less risky to rely on than the unconfined_t domain. Additionally, if
we define custom user/role, they would need to be manually defined
at the operating system level, adding more complexity to an already
non-standard and complex regression test.
Back-patch to 9.3. The regression tests will need more work before
working correctly on 9.2. Starting with 9.2, sepgsql has had dependencies
on libselinux versions that are only available on newer distros with
the changed set of policies (e.g. RHEL 7.x). On 9.1 sepgsql works
fine with the older distros with original policy set (e.g. RHEL 6.x),
and on which the existing regression tests work fine. We might want
eventually change 9.1 sepgsql regression tests to be more independent
from the underlying OS policies, however more work will be needed to
make that happen and it is not clear that it is worth the effort.
Kohei KaiGai with review by Adam Brightwell and me, commentary by
Stephen, Alvaro, Tom, Robert, and others.
The main change here is to call security_compute_create_name_raw()
rather than security_compute_create_raw(). This ups the minimum
requirement for libselinux from 2.0.99 to 2.1.10, but it looks
like most distributions will have picked that up before 9.3 is out.
KaiGai Kohei
... 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 the column name is an unqualified name, rather than table.column,
the error message complains about too many dotted names, which is
wrong. Report by Peter Eisentraut based on examination of the
sepgsql regression test output, but the problem also affects COMMENT.
New wording as suggested by Tom Lane.
This is intended as infrastructure to allow sepgsql to cooperate with
connection pooling software, by allowing the effective security label
to be set for each new connection.
KaiGai Kohei, reviewed by Yeb Havinga.
Álvaro Herrera