When changing the data type of a column of a partitioned table, craft
the ALTER SEQUENCE command only once. Partitions do not have identity
sequences of their own and thus do not need a ALTER SEQUENCE command
for each partition.
Fix getIdentitySequence() to fetch the identity sequence associated
with the top-level partitioned table when a Relation of a partition is
passed to it. While doing so, translate the attribute number of the
partition into the attribute number of the partitioned table.
Author: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Discussion: https://www.postgresql.org/message-id/3b8a9dc1-bbc7-0ef5-6863-c432afac7d59@gmail.com
This allows a RETURNING clause to be appended to a MERGE query, to
return values based on each row inserted, updated, or deleted. As with
plain INSERT, UPDATE, and DELETE commands, the returned values are
based on the new contents of the target table for INSERT and UPDATE
actions, and on its old contents for DELETE actions. Values from the
source relation may also be returned.
As with INSERT/UPDATE/DELETE, the output of MERGE ... RETURNING may be
used as the source relation for other operations such as WITH queries
and COPY commands.
Additionally, a special function merge_action() is provided, which
returns 'INSERT', 'UPDATE', or 'DELETE', depending on the action
executed for each row. The merge_action() function can be used
anywhere in the RETURNING list, including in arbitrary expressions and
subqueries, but it is an error to use it anywhere outside of a MERGE
query's RETURNING list.
Dean Rasheed, reviewed by Isaac Morland, Vik Fearing, Alvaro Herrera,
Gurjeet Singh, Jian He, Jeff Davis, Merlin Moncure, Peter Eisentraut,
and Wolfgang Walther.
Discussion: http://postgr.es/m/CAEZATCWePEGQR5LBn-vD6SfeLZafzEm2Qy_L_Oky2=qw2w3Pzg@mail.gmail.com
Commit a3c7a993d fixed some cases involving target columns that are
arrays or composites by applying transformAssignedExpr to the VALUES
entries, and then stripping off any assignment ArrayRefs or
FieldStores that the transformation added. But I forgot about domains
over arrays or composites :-(. Such cases would either fail with
surprising complaints about mismatched datatypes, or insert unexpected
coercions that could lead to odd results. To fix, extend the
stripping logic to get rid of CoerceToDomain if it's atop an ArrayRef
or FieldStore.
While poking at this, I realized that there's a poorly documented and
not-at-all-tested behavior nearby: we coerce each VALUES column to
the domain type separately, and rely on the rewriter to merge those
operations so that the domain constraints are checked only once.
If that merging did not happen, it's entirely possible that we'd get
unexpected domain constraint failures due to checking a
partially-updated container value. There's no bug there, but while
we're here let's improve the commentary about it and add some test
cases that explicitly exercise that behavior.
Per bug #18393 from Pablo Kharo. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18393-65fedb1a0de9260d@postgresql.org
as determined by include-what-you-use (IWYU)
While IWYU also suggests to *add* a bunch of #include's (which is its
main purpose), this patch does not do that. In some cases, a more
specific #include replaces another less specific one.
Some manual adjustments of the automatic result:
- IWYU currently doesn't know about includes that provide global
variable declarations (like -Wmissing-variable-declarations), so
those includes are being kept manually.
- All includes for port(ability) headers are being kept for now, to
play it safe.
- No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the
patch from exploding in size.
Note that this patch touches just *.c files, so nothing declared in
header files changes in hidden ways.
As a small example, in src/backend/access/transam/rmgr.c, some IWYU
pragma annotations are added to handle a special case there.
Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
This allows the target relation of MERGE to be an auto-updatable or
trigger-updatable view, and includes support for WITH CHECK OPTION,
security barrier views, and security invoker views.
A trigger-updatable view must have INSTEAD OF triggers for every type
of action (INSERT, UPDATE, and DELETE) mentioned in the MERGE command.
An auto-updatable view must not have any INSTEAD OF triggers. Mixing
auto-update and trigger-update actions (i.e., having a partial set of
INSTEAD OF triggers) is not supported.
Rule-updatable views are also not supported, since there is no
rewriter support for non-SELECT rules with MERGE operations.
Dean Rasheed, reviewed by Jian He and Alvaro Herrera.
Discussion: https://postgr.es/m/CAEZATCVcB1g0nmxuEc-A+gGB0HnfcGQNGYH7gS=7rq0u0zOBXA@mail.gmail.com
Previously, identity columns were disallowed on partitioned tables.
(The reason was mainly that no one had gotten around to working
through all the details to make it work.) This makes it work now.
Some details on the behavior:
* A newly created partition inherits identity property
The partitions of a partitioned table are integral part of the
partitioned table. A partition inherits identity columns from the
partitioned table. An identity column of a partition shares the
identity space with the corresponding column of the partitioned
table. In other words, the same identity column across all
partitions of a partitioned table share the same identity space.
This is effected by sharing the same underlying sequence.
When INSERTing directly into a partition, the sequence associated
with the topmost partitioned table is used to calculate the value of
the corresponding identity column.
In regular inheritance, identity columns and their properties in a
child table are independent of those in its parent tables. A child
table does not inherit identity columns or their properties
automatically from the parent. (This is unchanged.)
* Attached partition inherits identity column
A table being attached as a partition inherits the identity property
from the partitioned table. This should be fine since we expect
that the partition table's column has the same type as the
partitioned table's corresponding column. If the table being
attached is a partitioned table, the identity properties are
propagated down its partition hierarchy.
An identity column in the partitioned table is also marked as NOT
NULL. The corresponding column in the partition needs to be marked
as NOT NULL for the attach to succeed.
* Drop identity property when detaching partition
A partition's identity column shares the identity space
(i.e. underlying sequence) as the corresponding column of the
partitioned table. If a partition is detached it can longer share
the identity space as before. Hence the identity columns of the
partition being detached loose their identity property.
When identity of a column of a regular table is dropped it retains
the NOT NULL constraint that came with the identity property.
Similarly the columns of the partition being detached retain the NOT
NULL constraints that came with identity property, even though the
identity property itself is lost.
The sequence associated with the identity property is linked to the
partitioned table (and not the partition being detached). That
sequence is not dropped as part of detach operation.
* Partitions with their own identity columns are not allowed.
* The usual ALTER operations (add identity column, add identity
property to existing column, alter properties of an indentity
column, drop identity property) are supported for partitioned
tables. Changing a column only in a partitioned table or a
partition is not allowed; the change needs to be applied to the
whole partition hierarchy.
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/CAExHW5uOykuTC+C6R1yDSp=o8Q83jr8xJdZxgPkxfZ1Ue5RRGg@mail.gmail.com
This unifies some repetitive code.
Note: I didn't push the "not found" error message into the new
function, even though all existing callers would be able to make use
of it. Using the existing error handling as-is would probably require
exposing the Relation type via tupdesc.h, which doesn't seem
desirable. (Or even if we changed it to just report the OID, it would
inject the concept of a relation containing the tuple descriptor into
tupdesc.h, which might be a layering violation. Perhaps some further
improvements could be considered here separately.)
Discussion: https://www.postgresql.org/message-id/flat/52a125e4-ff9a-95f5-9f61-b87cf447e4da%40eisentraut.org
If MERGE executes an UPDATE action on a table with row-level security,
the code incorrectly applied the WITH CHECK clauses from the target
table's INSERT policies to new rows, instead of the clauses from the
table's UPDATE policies. In addition, it failed to check new rows
against the target table's SELECT policies, if SELECT permissions were
required (likely to always be the case).
In addition, if MERGE executes a DO NOTHING action for matched rows,
the code incorrectly applied the USING clauses from the target table's
DELETE policies to existing target tuples. These policies were applied
as checks that would throw an error, if they did not pass.
Fix this, so that a MERGE UPDATE action applies the same RLS policies
as a plain UPDATE query with a WHERE clause, and a DO NOTHING action
does not apply any RLS checks (other than adding clauses from SELECT
policies to the join).
Back-patch to v15, where MERGE was introduced.
Dean Rasheed, reviewed by Stephen Frost.
Security: CVE-2023-39418
47bb9db75 modified the ApplyRetrieveRule()'s conversion of a view's
original RTE_RELATION entry into an RTE_SUBQUERY one to retain relid,
rellockmode, and perminfoindex so that the executor can lock the view
and check its permissions. It seems better to also retain
relkind for cross-checking that the exception of an
RTE_SUBQUERY entry being allowed to carry relation details only
applies to views, so do so.
Bump catversion because this changes the output format of
RTE_SUBQUERY RTEs.
Suggested-by: David Steele <david@pgmasters.net>
Reviewed-by: David Steele <david@pgmasters.net>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/3953179e-9540-e5d1-a743-4bef368785b0%40pgmasters.net
rewriteRuleAction neglected to check for SubLink nodes in the
securityQuals of range table entries. This could lead to failing
to convert such a SubLink to a SubPlan, resulting in assertion
crashes or weird errors later in planning.
In passing, fix some poor coding in rewriteTargetView:
we should not pass the source parsetree's hasSubLinks
field to ReplaceVarsFromTargetList's outer_hasSubLinks.
ReplaceVarsFromTargetList knows enough to ignore that
when a Query node is passed, but it's still confusing
and bad precedent: if we did try to update that flag
we'd be updating a stale copy of the parsetree.
Per bug #17972 from Alexander Lakhin. This has been broken since
we added RangeTblEntry.securityQuals (although the presented test
case only fails back to 215b43cdc), so back-patch all the way.
Discussion: https://postgr.es/m/17972-f422c094237847d0@postgresql.org
Apparently some extensions are in the habit of calling
ChangeVarNodes() with INDEX_VAR as the rt_index to replace.
That worked before 2489d76c4, at least as long as there were
not PlaceHolderVars in the expression; but now it fails
because bms_is_member spits up. Add a test to avoid that.
Per report from Anton Melnikov, though this is not his
proposed patch.
Discussion: https://postgr.es/m/5b370a46-f6d2-373d-9dbc-0d55250e82c1@inbox.ru
Run pgindent, pgperltidy, and reformat-dat-files.
This set of diffs is a bit larger than typical. We've updated to
pg_bsd_indent 2.1.2, which properly indents variable declarations that
have multi-line initialization expressions (the continuation lines are
now indented one tab stop). We've also updated to perltidy version
20230309 and changed some of its settings, which reduces its desire to
add whitespace to lines to make assignments etc. line up. Going
forward, that should make for fewer random-seeming changes to existing
code.
Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
This fixes many spelling mistakes in comments, but a few references to
invalid parameter names, function names and option names too in comments
and also some in string constants
Also, fix an #undef that was undefining the incorrect definition
Author: Alexander Lakhin
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/d5f68d19-c0fc-91a9-118d-7c6a5a3f5fad@gmail.com
If a view is defined atop another view, and then CREATE OR REPLACE
VIEW is used to add columns to the lower view, then when the upper
view's referencing RTE is expanded by ApplyRetrieveRule we will have
a subquery RTE with fewer eref->colnames than output columns. This
confuses various code that assumes those lists are always in sync,
as they are in plain parser output.
We have seen such problems before (cf commit d5b760ecb), and now
I think the time has come to do what was speculated about in that
commit: let's make ApplyRetrieveRule synthesize some column names to
preserve the invariant that holds in parser output. Otherwise we'll
be chasing this class of bugs indefinitely. Moreover, it appears from
testing that this actually gives us better results in the test case
d5b760ecb added, and likely in other corner cases that we lack
coverage for.
In HEAD, I replaced d5b760ecb's hack to make expandRTE exit early with
an elog(ERROR) call, since the case is now presumably unreachable.
But it seems like changing that in back branches would bring more risk
than benefit, so there I just updated the comment.
Per bug #17811 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/17811-d31686b78f0dffc9@postgresql.org
If a rule action contains a subquery that refers to columns from OLD
or NEW, then those are really lateral references, and the planner will
complain if it sees such things in a subquery that isn't marked as
lateral. However, at rule-definition time, the user isn't required to
mark the subquery with LATERAL, and so it can fail when the rule is
used.
Fix this by marking such subqueries as lateral in the rewriter, at the
point where they're used.
Dean Rasheed and Tom Lane, per report from Alexander Lakhin.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/5e09da43-aaba-7ea7-0a51-a2eb981b058b%40gmail.com
Given an updatable view with a DO ALSO INSERT ... SELECT rule, a
multi-row INSERT ... VALUES query on the view fails if the VALUES list
contains any DEFAULTs that are not replaced by view defaults. This
manifests as an "unrecognized node type" error, or an Assert failure,
in an assert-enabled build.
The reason is that when RewriteQuery() attempts to replace the
remaining DEFAULT items with NULLs in any product queries, using
rewriteValuesRTEToNulls(), it assumes that the VALUES RTE is located
at the same rangetable index in each product query. However, if the
product query is an INSERT ... SELECT, then the VALUES RTE is actually
in the SELECT part of that query (at the same index), rather than the
top-level product query itself.
Fix, by descending to the SELECT in such cases. Note that we can't
simply use getInsertSelectQuery() for this, since that expects to be
given a raw rule action with OLD and NEW placeholder entries, so we
duplicate its logic instead.
While at it, beef up the checks in getInsertSelectQuery() by checking
that the jointree->fromlist node is indeed a RangeTblRef, and that the
RTE it points to has rtekind == RTE_SUBQUERY.
Per bug #17803, from Alexander Lakhin. Back-patch to all supported
branches.
Dean Rasheed, reviewed by Tom Lane.
Discussion: https://postgr.es/m/17803-53c63ed4ecb4eac6%40postgresql.org
Traditionally we used the same Var struct to represent the value
of a table column everywhere in parse and plan trees. This choice
predates our support for SQL outer joins, and it's really a pretty
bad idea with outer joins, because the Var's value can depend on
where it is in the tree: it might go to NULL above an outer join.
So expression nodes that are equal() per equalfuncs.c might not
represent the same value, which is a huge correctness hazard for
the planner.
To improve this, decorate Var nodes with a bitmapset showing
which outer joins (identified by RTE indexes) may have nulled
them at the point in the parse tree where the Var appears.
This allows us to trust that equal() Vars represent the same value.
A certain amount of klugery is still needed to cope with cases
where we re-order two outer joins, but it's possible to make it
work without sacrificing that core principle. PlaceHolderVars
receive similar decoration for the same reason.
In the planner, we include these outer join bitmapsets into the relids
that an expression is considered to depend on, and in consequence also
add outer-join relids to the relids of join RelOptInfos. This allows
us to correctly perceive whether an expression can be calculated above
or below a particular outer join.
This change affects FDWs that want to plan foreign joins. They *must*
follow suit when labeling foreign joins in order to match with the
core planner, but for many purposes (if postgres_fdw is any guide)
they'd prefer to consider only base relations within the join.
To support both requirements, redefine ForeignScan.fs_relids as
base+OJ relids, and add a new field fs_base_relids that's set up by
the core planner.
Large though it is, this commit just does the minimum necessary to
install the new mechanisms and get check-world passing again.
Follow-up patches will perform some cleanup. (The README additions
and comments mention some stuff that will appear in the follow-up.)
Patch by me; thanks to Richard Guo for review.
Discussion: https://postgr.es/m/830269.1656693747@sss.pgh.pa.us
The rule system needs "old" and/or "new" pseudo-RTEs in rule actions
that are ON INSERT/UPDATE/DELETE. Historically it's put such entries
into the ON SELECT rules of views as well, but those are really quite
vestigial. The only thing we've used them for is to carry the
view's relid forward to AcquireExecutorLocks (so that we can
re-lock the view to verify it hasn't changed before re-using a plan)
and to carry its relid and permissions data forward to execution-time
permissions checks. What we can do instead of that is to retain
these fields of the RTE_RELATION RTE for the view even after we
convert it to an RTE_SUBQUERY RTE. This requires a tiny amount of
extra complication in the planner and AcquireExecutorLocks, but on
the other hand we can get rid of the logic that moves that data from
one place to another.
The principal immediate benefit of doing this, aside from a small
saving in the pg_rewrite data for views, is that these pseudo-RTEs
no longer trigger ruleutils.c's heuristic about qualifying variable
names when the rangetable's length is more than 1. That results
in quite a number of small simplifications in regression test outputs,
which are all to the good IMO.
Bump catversion because we need to dump a few more fields of
RTE_SUBQUERY RTEs. While those will always be zeroes anyway in
stored rules (because we'd never populate them until query rewrite)
they are useful for debugging, and it seems like we'd better make
sure to transmit such RTEs accurately in plans sent to parallel
workers. I don't think the executor actually examines these fields
after startup, but someday it might.
This is a second attempt at committing 1b4d280ea. The difference
from the first time is that now we can add some filtering rules to
AdjustUpgrade.pm to allow cross-version upgrade testing to pass
despite all the cosmetic changes in CREATE VIEW outputs.
Amit Langote (filtering rules by me)
Discussion: https://postgr.es/m/CA+HiwqEf7gPN4Hn+LoZ4tP2q_Qt7n3vw7-6fJKOf92tSEnX6Gg@mail.gmail.com
Discussion: https://postgr.es/m/891521.1673657296@sss.pgh.pa.us
This reverts commit 1b4d280ea1.
It's broken the buildfarm members that run cross-version-upgrade tests,
because they're not prepared to deal with cosmetic differences between
CREATE VIEW commands emitted by older servers and HEAD. Even if we had
a solution to that, which we don't, it'd take some time to roll it out
to the affected animals. This improvement isn't valuable enough to
justify addressing that problem on an emergency basis, so revert it
for now.
The rule system needs "old" and/or "new" pseudo-RTEs in rule actions
that are ON INSERT/UPDATE/DELETE. Historically it's put such entries
into the ON SELECT rules of views as well, but those are really quite
vestigial. The only thing we've used them for is to carry the
view's relid forward to AcquireExecutorLocks (so that we can
re-lock the view to verify it hasn't changed before re-using a plan)
and to carry its relid and permissions data forward to execution-time
permissions checks. What we can do instead of that is to retain
these fields of the RTE_RELATION RTE for the view even after we
convert it to an RTE_SUBQUERY RTE. This requires a tiny amount of
extra complication in the planner and AcquireExecutorLocks, but on
the other hand we can get rid of the logic that moves that data from
one place to another.
The principal immediate benefit of doing this, aside from a small
saving in the pg_rewrite data for views, is that these pseudo-RTEs
no longer trigger ruleutils.c's heuristic about qualifying variable
names when the rangetable's length is more than 1. That results
in quite a number of small simplifications in regression test outputs,
which are all to the good IMO.
Bump catversion because we need to dump a few more fields of
RTE_SUBQUERY RTEs. While those will always be zeroes anyway in
stored rules (because we'd never populate them until query rewrite)
they are useful for debugging, and it seems like we'd better make
sure to transmit such RTEs accurately in plans sent to parallel
workers. I don't think the executor actually examines these fields
after startup, but someday it might.
Amit Langote
Discussion: https://postgr.es/m/CA+HiwqEf7gPN4Hn+LoZ4tP2q_Qt7n3vw7-6fJKOf92tSEnX6Gg@mail.gmail.com
We were identifying the updatable generated columns of inheritance
children by transposing the calculation made for their parent.
However, there's nothing that says a traditional-inheritance child
can't have generated columns that aren't there in its parent, or that
have different dependencies than are in the parent's expression.
(At present it seems that we don't enforce that for partitioning
either, which is likely wrong to some degree or other; but the case
clearly needs to be handled with traditional inheritance.)
Hence, drop the very-klugy-anyway "extraUpdatedCols" RTE field
in favor of identifying which generated columns depend on updated
columns during executor startup. In HEAD we can remove
extraUpdatedCols altogether; in back branches, it's still there but
always empty. Another difference between the HEAD and back-branch
versions of this patch is that in HEAD we can add the new bitmap field
to ResultRelInfo, but that would cause an ABI break in back branches.
Like 4b3e37993, add a List field at the end of struct EState instead.
Back-patch to v13. The bogus calculation is also being made in v12,
but it doesn't have the same visible effect because we don't use it
to decide which generated columns to recalculate; as a consequence of
which the patch doesn't apply easily. I think that there might still
be a demonstrable bug associated with trigger firing conditions, but
that's such a weird corner-case usage that I'm content to leave it
unfixed in v12.
Amit Langote and Tom Lane
Discussion: https://postgr.es/m/CA+HiwqFshLKNvQUd1DgwJ-7tsTp=dwv7KZqXC4j2wYBV1aCDUA@mail.gmail.com
Discussion: https://postgr.es/m/2793383.1672944799@sss.pgh.pa.us
Currently, information about the permissions to be checked on relations
mentioned in a query is stored in their range table entries. So the
executor must scan the entire range table looking for relations that
need to have permissions checked. This can make the permission checking
part of the executor initialization needlessly expensive when many
inheritance children are present in the range range. While the
permissions need not be checked on the individual child relations, the
executor still must visit every range table entry to filter them out.
This commit moves the permission checking information out of the range
table entries into a new plan node called RTEPermissionInfo. Every
top-level (inheritance "root") RTE_RELATION entry in the range table
gets one and a list of those is maintained alongside the range table.
This new list is initialized by the parser when initializing the range
table. The rewriter can add more entries to it as rules/views are
expanded. Finally, the planner combines the lists of the individual
subqueries into one flat list that is passed to the executor for
checking.
To make it quick to find the RTEPermissionInfo entry belonging to a
given relation, RangeTblEntry gets a new Index field 'perminfoindex'
that stores the corresponding RTEPermissionInfo's index in the query's
list of the latter.
ExecutorCheckPerms_hook has gained another List * argument; the
signature is now:
typedef bool (*ExecutorCheckPerms_hook_type) (List *rangeTable,
List *rtePermInfos,
bool ereport_on_violation);
The first argument is no longer used by any in-core uses of the hook,
but we leave it in place because there may be other implementations that
do. Implementations should likely scan the rtePermInfos list to
determine which operations to allow or deny.
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqGjJDmUhDSfv-U2qhKJjt9ST7Xh9JXC_irsAQ1TAUsJYg@mail.gmail.com
When updating a relation with a rule whose action performed an INSERT
from a multi-row VALUES list, the rewriter might skip processing the
VALUES list, and therefore fail to replace any DEFAULTs in it. This
would lead to an "unrecognized node type" error.
The reason was that RewriteQuery() assumed that a query doing an
INSERT from a multi-row VALUES list would necessarily only have one
item in its fromlist, pointing to the VALUES RTE to read from. That
assumption is correct for the original query, but not for product
queries produced for rule actions. In such cases, there may be
multiple items in the fromlist, possibly including multiple VALUES
RTEs.
What is required instead is for RewriteQuery() to skip any RTEs from
the product query's originating query, which might include one or more
already-processed VALUES RTEs. What's left should then include at most
one VALUES RTE (from the rule action) to be processed.
Patch by me. Thanks to Tom Lane for reviewing.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAEZATCV39OOW7LAR_Xq4i%2BLc1Byux%3DeK3Q%3DHD_pF1o9LBt%3DphA%40mail.gmail.com
Up to now we have allowed manual creation of an ON SELECT rule on
a table to convert it into a view. That was never anything but a
horrid, error-prone hack though. pg_dump used to rely on that
behavior to deal with cases involving circular dependencies,
where a dependency loop could be broken by separating the creation
of a view from installation of its ON SELECT rule. However, we
changed pg_dump to use CREATE OR REPLACE VIEW for that in commit
d8c05aff5 (which was later back-patched as far as 9.4), so there's
not a good argument anymore for continuing to support the behavior.
The proximate reason for axing it now is that we found that the
new statistics code has failure modes associated with the relkind
change caused by this behavior. We'll patch around that in v15,
but going forward it seems like a better idea to get rid of the
need to support relkind changes.
Discussion: https://postgr.es/m/CALDaNm2yXz+zOtv7y5zBd5WKT8O0Ld3YxikuU3dcyCvxF7gypA@mail.gmail.com
A future commit will move the checkAsUser field from RangeTblEntry
to a new node that, unlike RTEs, will only be created for tables
mentioned in the query but not for the inheritance child relations
added to the query by the planner. So, checkAsUser value for a
given child relation will have to be obtained by referring to that
for its ancestor mentioned in the query.
In preparation, it seems better to expand the use of RelOptInfo.userid
during planning in place of rte->checkAsUser so that there will be
fewer places to adjust for the above change.
Given that the child-to-ancestor mapping is not available during the
execution of a given "child" ForeignScan node, add a checkAsUser
field to ForeignScan to carry the child relation's RelOptInfo.userid.
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqGFCs2uq7VRKi7g+FFKbP6Ea_2_HkgZb2HPhUfaAKT3ng@mail.gmail.com
Instead of dozens of mostly-duplicate pg_foo_ownercheck() functions,
write one common function object_ownercheck() that can handle almost
all of them. We already have all the information we need, such as
which system catalog corresponds to which catalog table and which
column is the owner column.
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://www.postgresql.org/message-id/flat/95c30f96-4060-2f48-98b5-a4392d3b6066@enterprisedb.com
DefineQueryRewrite() has long required that ON SELECT rules be named
"_RETURN". But we overlooked the converse case: we should forbid
non-ON-SELECT rules that are named "_RETURN". In particular this
prevents using CREATE OR REPLACE RULE to overwrite a view's _RETURN
rule with some other kind of rule, thereby breaking the view.
Per bug #17646 from Kui Liu. Back-patch to all supported branches.
Discussion: https://postgr.es/m/17646-70c93cfa40365776@postgresql.org
DEFAULT markers appearing in an INSERT on an updatable view
could be mis-processed if they were in a multi-row VALUES clause.
This would lead to strange errors such as "cache lookup failed
for type NNNN", or in older branches even to crashes.
The cause is that commit 41531e42d tried to re-use rewriteValuesRTE()
to remove any SetToDefault nodes (that hadn't previously been replaced
by the view's own default values) appearing in "product" queries,
that is DO ALSO queries. That's fundamentally wrong because the
DO ALSO queries might not even be INSERTs; and even if they are,
their targetlists don't necessarily match the view's column list,
so that almost all the logic in rewriteValuesRTE() is inapplicable.
What we want is a narrow focus on replacing any such nodes with NULL
constants. (That is, in this context we are interpreting the defaults
as being strictly those of the view itself; and we already replaced
any that aren't NULL.) We could add still more !force_nulls tests
to further lobotomize rewriteValuesRTE(); but it seems cleaner to
split out this case to a new function, restoring rewriteValuesRTE()
to the charter it had before.
Per bug #17633 from jiye_sw. Patch by me, but thanks to
Richard Guo and Japin Li for initial investigation.
Back-patch to all supported branches, as the previous fix was.
Discussion: https://postgr.es/m/17633-98cc85e1fa91e905@postgresql.org
Autoconf is showing its age, fewer and fewer contributors know how to wrangle
it. Recursive make has a lot of hard to resolve dependency issues and slow
incremental rebuilds. Our home-grown MSVC build system is hard to maintain for
developers not using Windows and runs tests serially. While these and other
issues could individually be addressed with incremental improvements, together
they seem best addressed by moving to a more modern build system.
After evaluating different build system choices, we chose to use meson, to a
good degree based on the adoption by other open source projects.
We decided that it's more realistic to commit a relatively early version of
the new build system and mature it in tree.
This commit adds an initial version of a meson based build system. It supports
building postgres on at least AIX, FreeBSD, Linux, macOS, NetBSD, OpenBSD,
Solaris and Windows (however only gcc is supported on aix, solaris). For
Windows/MSVC postgres can now be built with ninja (faster, particularly for
incremental builds) and msbuild (supporting the visual studio GUI, but
building slower).
Several aspects (e.g. Windows rc file generation, PGXS compatibility, LLVM
bitcode generation, documentation adjustments) are done in subsequent commits
requiring further review. Other aspects (e.g. not installing test-only
extensions) are not yet addressed.
When building on Windows with msbuild, builds are slower when using a visual
studio version older than 2019, because those versions do not support
MultiToolTask, required by meson for intra-target parallelism.
The plan is to remove the MSVC specific build system in src/tools/msvc soon
after reaching feature parity. However, we're not planning to remove the
autoconf/make build system in the near future. Likely we're going to keep at
least the parts required for PGXS to keep working around until all supported
versions build with meson.
Some initial help for postgres developers is at
https://wiki.postgresql.org/wiki/Meson
With contributions from Thomas Munro, John Naylor, Stone Tickle and others.
Author: Andres Freund <andres@anarazel.de>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Author: Peter Eisentraut <peter@eisentraut.org>
Reviewed-By: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/20211012083721.hvixq4pnh2pixr3j@alap3.anarazel.de
In a similar effort to f01592f91, here we're targetting fixing the
warnings where we've deemed the shadowing variable to serve a close enough
purpose to the shadowed variable just to reuse the shadowed version and
not declare the shadowing variable at all.
By my count, this takes the warning count from 106 down to 71.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20220825020839.GT2342@telsasoft.com
The standard way to check for list emptiness is to compare the
List pointer to NIL; our list code goes out of its way to ensure
that that is the only representation of an empty list. (An
acceptable alternative is a plain boolean test for non-null
pointer, but explicit mention of NIL is usually preferable.)
Various places didn't get that memo and expressed the condition
with list_length(), which might not be so bad except that there
were such a variety of ways to check it exactly: equal to zero,
less than or equal to zero, less than one, yadda yadda. In the
name of code readability, let's standardize all those spellings
as "list == NIL" or "list != NIL". (There's probably some
microscopic efficiency gain too, though few of these look to be
at all performance-critical.)
A very small number of cases were left as-is because they seemed
more consistent with other adjacent list_length tests that way.
Peter Smith, with bikeshedding from a number of us
Discussion: https://postgr.es/m/CAHut+PtQYe+ENX5KrONMfugf0q6NHg4hR5dAhqEXEc2eefFeig@mail.gmail.com
This replaces all MemSet() calls with struct initialization where that
is easily and obviously possible. (For example, some cases have to
worry about padding bits, so I left those.)
(The same could be done with appropriate memset() calls, but this
patch is part of an effort to phase out MemSet(), so it doesn't touch
memset() calls.)
Reviewed-by: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/9847b13c-b785-f4e2-75c3-12ec77a3b05c@enterprisedb.com
This function looks for a reference to the recursive WITH CTE,
but it checked only the CTE name not ctelevelsup, so that it could
seize on a lower CTE that happened to have the same name. This
would result in planner failures later, either weird errors such as
"could not find attribute 2 in subquery targetlist", or crashes
or assertion failures. The code also merely Assert'ed that it found
a matching entry, which is not guaranteed at all by the parser.
Per bugs #17320 and #17318 from Zhiyong Wu.
Thanks to Kyotaro Horiguchi for investigation.
Discussion: https://postgr.es/m/17320-70e37868182512ab@postgresql.org
Discussion: https://postgr.es/m/17318-2eb65a3a611d2368@postgresql.org
MERGE performs actions that modify rows in the target table using a
source table or query. MERGE provides a single SQL statement that can
conditionally INSERT/UPDATE/DELETE rows -- a task that would otherwise
require multiple PL statements. For example,
MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
DO NOTHING;
MERGE works with regular tables, partitioned tables and inheritance
hierarchies, including column and row security enforcement, as well as
support for row and statement triggers and transition tables therein.
MERGE is optimized for OLTP and is parameterizable, though also useful
for large scale ETL/ELT. MERGE is not intended to be used in preference
to existing single SQL commands for INSERT, UPDATE or DELETE since there
is some overhead. MERGE can be used from PL/pgSQL.
MERGE does not support targetting updatable views or foreign tables, and
RETURNING clauses are not allowed either. These limitations are likely
fixable with sufficient effort. Rewrite rules are also not supported,
but it's not clear that we'd want to support them.
Author: Pavan Deolasee <pavan.deolasee@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Reviewed-by: Peter Geoghegan <pg@bowt.ie> (earlier versions)
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Japin Li <japinli@hotmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
Discussion: https://postgr.es/m/20201231134736.GA25392@alvherre.pgsql
A security invoker view checks permissions for accessing its
underlying base relations using the privileges of the user of the
view, rather than the privileges of the view owner. Additionally, if
any of the base relations are tables with RLS enabled, the policies of
the user of the view are applied, rather than those of the view owner.
This allows views to be defined without giving away additional
privileges on the underlying base relations, and matches a similar
feature available in other database systems.
It also allows views to operate more naturally with RLS, without
affecting the assignments of policies to users.
Christoph Heiss, with some additional hacking by me. Reviewed by
Laurenz Albe and Wolfgang Walther.
Discussion: https://postgr.es/m/b66dd6d6-ad3e-c6f2-8b90-47be773da240%40cybertec.at
If a RowExpr is marked as returning a named composite type, we aren't
going to consult its colnames list; we'll use the attribute names
shown for the type in pg_attribute. Hence, skip storing that list,
to save a few nanoseconds when copying the expression tree around.
Discussion: https://postgr.es/m/2950001.1638729947@sss.pgh.pa.us
If we copy data-modifying CTEs from the original query to a replacement
query (from a DO INSTEAD rule), we must set hasModifyingCTE properly
in the replacement query. Failure to do this can cause various
unpleasantness, such as unsafe usage of parallel plans. The code also
neglected to propagate hasRecursive, though that's only cosmetic at
the moment.
A difficulty arises if the rule action is an INSERT...SELECT. We
attach the original query's RTEs and CTEs to the sub-SELECT Query, but
data-modifying CTEs are only allowed to appear in the topmost Query.
For the moment, throw an error in such cases. It would probably be
possible to avoid this error by attaching the CTEs to the top INSERT
Query instead; but that would require a bunch of new code to adjust
ctelevelsup references. Given the narrowness of the use-case, and
the need to back-patch this fix, it does not seem worth the trouble
for now. We can revisit this if we get field complaints.
Per report from Greg Nancarrow. Back-patch to all supported branches.
(The test case added here does not fail before v10, but there are
plenty of places checking top-level hasModifyingCTE in 9.6, so I have
no doubt that this code change is necessary there too.)
Greg Nancarrow and Tom Lane
Discussion: https://postgr.es/m/CAJcOf-f68DT=26YAMz_i0+Au3TcLO5oiHY5=fL6Sfuits6r+_w@mail.gmail.com
Discussion: https://postgr.es/m/CAJcOf-fAdj=nDKMsRhQzndm-O13NY4dL6xGcEvdX5Xvbbi0V7g@mail.gmail.com
Commit 01e658fa74 added hash support for row types. This also added
support for hashing anonymous record types, using the same approach
that the type cache uses for comparison support for record types: It
just reports that it works, but it might fail at run time if a
component type doesn't actually support the operation. We get away
with that for comparison because most types support that. But some
types don't support hashing, so the current state can result in
failures at run time where the planner chooses hashing over sorting,
whereas that previously worked if only sorting was an option.
We do, however, want the record hashing support for path tracking in
recursive unions, and the SEARCH and CYCLE clauses built on that. In
that case, hashing is the only plan option. So enable that, this
commit implements the following approach: The type cache does not
report that hashing is available for the record type. This undoes
that part of 01e658fa74. Instead, callers that require hashing no
matter what can override that result themselves. This patch only
touches the callers to make the aforementioned recursive query cases
work, namely the parse analysis of unions, as well as the hash_array()
function.
Reported-by: Sait Talha Nisanci <sait.nisanci@microsoft.com>
Bug: #17158
Discussion: https://www.postgresql.org/message-id/flat/17158-8a2ba823982537a4%40postgresql.org
Since the executor can't cope with a utility statement appearing
as a node of a plan tree, we can't support cases where a rewrite
rule inserts a NOTIFY into an INSERT/UPDATE/DELETE command appearing
in a WITH clause of a larger query. (One can imagine ways around
that, but it'd be a new feature not a bug fix, and so far there's
been no demand for it.) RewriteQuery checked for this, but it
missed the case where the DML command rewrites to *only* a NOTIFY.
That'd lead to crashes later on in planning. Add the missed check,
and improve the level of testing of this area.
Per bug #17094 from Yaoguang Chen. It's been busted since WITH
was introduced, so back-patch to all supported branches.
Discussion: https://postgr.es/m/17094-bf15dff55eaf2e28@postgresql.org
Peter Eisentraut
Dean Rasheed
Tom Lane
Bruce Momjian
Amit Langote
David Rowley
Andrew Dunstan
Alvaro Herrera
Andres Freund
John Naylor