Commit Graph

1388 Commits

Author SHA1 Message Date
Michael Paquier 2a507f6fd8 Mark more nodes with attribute no_query_jumble
This commit removes most of the Plan and Path nodes, which should never
be included in the query jumbling because we ignore these in Query
nodes.  This is facilitated by making no_query_jumble an inherited
attribute, like no_copy, no_equal and no_read when the supertype of a
node is found as marked with that.

RawStmt is not used in parsed queries, so it can be removed from the
query jumbling.  A couple of nodes defined in pathnodes.h, plannodes.h
and primnodes.h with NodeTag as supertype need to be marked
individually.

Forcing the execution of the query jumbling code with compute_query_id =
auto while pg_stat_statements is loaded brings the code coverage of
queryjumblefuncs.funcs.c to 95.6%.

The core code does not yet include a way to enforce the execution in
query jumbling except in pg_stat_statements, so the numbers I am
mentioning above will not reflect on the default coverage report with
just what is done in this commit.

Reported-by: Tom Lane
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/3344827.1675809127@sss.pgh.pa.us
2023-02-13 09:07:33 +09:00
Peter Eisentraut aa69541046 Remove useless casts to (void *) in arguments of some system functions
The affected functions are: bsearch, memcmp, memcpy, memset, memmove,
qsort, repalloc

Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/fd9adf5d-b1aa-e82f-e4c7-263c30145807%40enterprisedb.com
2023-02-07 06:57:59 +01:00
Michael Paquier 9ba37b2cb6 Include values of A_Const nodes in query jumbling
Like the implementation for node copy, write and read, this node
requires a custom implementation so as the query jumbling is able to
consider the correct value assigned to it, depending on its type (int,
float, bool, string, bitstring).

Based on a dump of pg_stat_statements from the regression database, this
would confuse the query jumbling of the following queries:
- SET.
- COPY TO with SELECT queries.
- START TRANSACTION with different isolation levels.
- ALTER TABLE with default expressions.
- CREATE TABLE with partition bounds.

Note that there may be a long-term argument in tracking the location of
such nodes so as query strings holding such nodes could be normalized,
but this is left as a separate discussion.

Oversight in 3db72eb.

Discussion: https://postgr.es/m/Y9+HuYslMAP6yyPb@paquier.xyz
2023-02-07 09:03:54 +09:00
Michael Paquier 3db72ebcbe Generate code for query jumbling through gen_node_support.pl
This commit changes the query jumbling code in queryjumblefuncs.c to be
generated automatically based on the information of the nodes in the
headers of src/include/nodes/ by using gen_node_support.pl.  This
approach offers many advantages:
- Support for query jumbling for all the utility statements, based on the
state of their parsed Nodes and not only their query string.  This will
greatly ease the switch to normalize the information of some DDLs, like
SET or CALL for example (this is left unchanged and should be part of a
separate discussion).  With this feature, the number of entries stored
for utilities in pg_stat_statements is reduced (for example now
"CHECKPOINT" and "checkpoint" mean the same thing with the same query
ID).
- Documentation of query jumbling directly in the structure definition
of the nodes.  Since this code has been introduced in pg_stat_statements
and then moved to code, the reasons behind the choices of what should be
included in the jumble are rather sparse.  Note that some explanation is
added for the most relevant parts, as a start.
- Overall code reduction and more consistency with the other parts
generating read, write and copy depending on the nodes.

The query jumbling is controlled by a couple of new node attributes,
documented in nodes/nodes.h:
- custom_query_jumble, to mark a Node as having a custom
implementation.
- no_query_jumble, to ignore entirely a Node.
- query_jumble_ignore, to ignore a field in a Node.
- query_jumble_location, to mark a location in a Node, for
normalization.  This can apply only to int fields, with "location" in
their name (only Const as of this commit).

There should be no compatibility impact on pg_stat_statements, as the
new code applies the jumbling to the same fields for each node (its
regression tests have no modification, for one).

Some benchmark of the query jumbling between HEAD and this commit for
SELECT and DMLs has proved that this new code does not cause a
performance regression, with computation times close for both methods.
For utility queries, the new method is slower than the previous method
of calculating a hash of the query string, though we are talking about
extra ns-level changes based on what I measured, which is unnoticeable
even for OLTP workloads as a query ID is calculated once per query
post-parse analysis.

Author: Michael Paquier
Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
2023-01-31 15:24:05 +09:00
Tom Lane 3bef56e116 Invent "join domains" to replace the below_outer_join hack.
EquivalenceClasses are now understood as applying within a "join
domain", which is a set of inner-joined relations (possibly underneath
an outer join).  We no longer need to treat an EC from below an outer
join as a second-class citizen.

I have hopes of eventually being able to treat outer-join clauses via
EquivalenceClasses, by means of only applying deductions within the
EC's join domain.  There are still problems in the way of that, though,
so for now the reconsider_outer_join_clause logic is still here.

I haven't been able to get rid of RestrictInfo.is_pushed_down either,
but I wonder if that could be recast using JoinDomains.

I had to hack one test case in postgres_fdw.sql to make it still test
what it was meant to, because postgres_fdw is inconsistent about
how it deals with quals containing non-shippable expressions; see
https://postgr.es/m/1691374.1671659838@sss.pgh.pa.us.  That should
be improved, but I don't think it's within the scope of this patch
series.

Patch by me; thanks to Richard Guo for review.

Discussion: https://postgr.es/m/830269.1656693747@sss.pgh.pa.us
2023-01-30 13:50:25 -05:00
Tom Lane 2489d76c49 Make Vars be outer-join-aware.
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
2023-01-30 13:16:20 -05:00
Michael Paquier 8eba3e3f02 Move queryjumble.c code to src/backend/nodes/
This will ease a follow-up move that will generate automatically this
code.  The C file is renamed, for consistency with the node-related
files whose code are generated by gen_node_support.pl:
- queryjumble.c -> queryjumblefuncs.c
- utils/queryjumble.h -> nodes/queryjumble.h

Per a suggestion from Peter Eisentraut.

Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
2023-01-21 11:48:37 +09:00
Tom Lane 47bb9db759 Get rid of the "new" and "old" entries in a view's rangetable.
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
2023-01-18 13:23:57 -05:00
Tom Lane f0e6d6d3c9 Revert "Get rid of the "new" and "old" entries in a view's rangetable."
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.
2023-01-11 23:01:22 -05:00
Tom Lane 1b4d280ea1 Get rid of the "new" and "old" entries in a view's rangetable.
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
2023-01-11 19:41:09 -05:00
Tom Lane 3f7836ff65 Fix calculation of which GENERATED columns need to be updated.
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
2023-01-05 14:12:17 -05:00
Bruce Momjian c8e1ba736b Update copyright for 2023
Backpatch-through: 11
2023-01-02 15:00:37 -05:00
Andrew Dunstan 8284cf5f74 Add copyright notices to meson files
Discussion: https://postgr.es/m/222b43a5-2fb3-2c1b-9cd0-375d376c8246@dunslane.net
2022-12-20 07:54:39 -05:00
Tom Lane d9f7f5d32f Create infrastructure for "soft" error reporting.
Postgres' standard mechanism for reporting errors (ereport() or elog())
is used for all sorts of error conditions.  This means that throwing
an exception via ereport(ERROR) requires an expensive transaction or
subtransaction abort and cleanup, since the exception catcher dare not
make many assumptions about what has gone wrong.  There are situations
where we would rather have a lighter-weight mechanism for dealing
with errors that are known to be safe to recover from without a full
transaction cleanup.  This commit creates infrastructure to let us
adapt existing error-reporting code for that purpose.  See the
included documentation changes for details.  Follow-on commits will
provide test code and usage examples.

The near-term plan is to convert most if not all datatype input
functions to report invalid input "softly".  This will enable
implementing some SQL/JSON features cleanly and without the cost
of subtransactions, and it will also allow creating COPY options
to deal with bad input without cancelling the whole COPY.

This patch is mostly by me, but it owes very substantial debt to
earlier work by Nikita Glukhov, Andrew Dunstan, and Amul Sul.
Thanks also to Andres Freund for review.

Discussion: https://postgr.es/m/3bbbb0df-7382-bf87-9737-340ba096e034@postgrespro.ru
2022-12-09 09:58:38 -05:00
Alvaro Herrera a61b1f7482
Rework query relation permission checking
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
2022-12-06 16:09:24 +01:00
Tom Lane 4c689a69ee Remove gen_node_support.pl's special treatment of EquivalenceClasses.
It seems better to deal with this by explicit annotations on the
fields in question, instead of magic knowledge embedded in the
script.  While that creates a risk-of-omission from failing to
annotate fields, the preceding commit should catch any such
oversights.

Discussion: https://postgr.es/m/263413.1669513145@sss.pgh.pa.us
2022-12-02 15:20:30 -05:00
Tom Lane b6bd5def3a Add some error cross-checks to gen_node_support.pl.
Check that if we generate a call to copy, compare, write, or read
a specific node type, that node type does have the appropriate
support function.  (This doesn't protect against trying to invoke
nonexistent code when considering generic field types such as
"Node *", but it seems like a useful check anyway.)

Check that array_size() refers to a field appearing earlier in
the struct.  Aside from catching obvious errors like a misspelled
field name, this protects against a more subtle mistake: if the
size field appears later in the struct than the array field, then
compare and read functions would misbehave.  There is actually
exactly that situation in PlannerInfo, but it's okay since we
do not need compare or read functionality for that (today anyway).

Discussion: https://postgr.es/m/263413.1669513145@sss.pgh.pa.us
2022-12-02 15:09:51 -05:00
Andrew Dunstan 50617a9aa3 Fix gen_node_support.pl for changed AclMode size
omitted from 7b378237aa, mea culpa.

Complaint and fix from Amit Langote.
2022-11-25 08:55:56 -05:00
Andrew Dunstan 7b378237aa Expand AclMode to 64 bits
We're running out of bits for new permissions. This change doubles the
number of permissions we can accomodate from 16 to 32, so the
forthcoming new ones for vacuum/analyze don't exhaust the pool.

Nathan Bossart

Reviewed by: Bharath Rupireddy, Kyotaro Horiguchi, Stephen Frost, Robert
Haas, Mark Dilger, Tom Lane, Corey Huinker, David G. Johnston, Michael
Paquier.

Discussion: https://postgr.es/m/20220722203735.GB3996698@nathanxps13
2022-11-23 14:43:16 -05:00
Michael Paquier f193883fc9 Replace SQLValueFunction by COERCE_SQL_SYNTAX
This switch impacts 9 patterns related to a SQL-mandated special syntax
for function calls:
- LOCALTIME [ ( typmod ) ]
- LOCALTIMESTAMP [ ( typmod ) ]
- CURRENT_TIME [ ( typmod ) ]
- CURRENT_TIMESTAMP [ ( typmod ) ]
- CURRENT_DATE

Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to provide backward-compatibility and making this
change transparent for the end-user (for example for the attribute
generated when a keyword is specified in a SELECT or in a FROM clause
without an alias, or when specifying something else than an Iconst to
the parser).

The parser included a set of checks coming from the files in charge of
holding the C functions used for the SQLValueFunction calls (as of
transformSQLValueFunction()), which are now moved within each function's
execution path, so this reduces the dependencies between the execution
and the parsing steps.  As of this change, all the SQL keywords use the
same paths for their work, relying only on COERCE_SQL_SYNTAX.  Like
fb32748, no performance difference has been noticed, while the perf
profiles get reduced with ExecEvalSQLValueFunction() gone.

Bump catalog version.

Reviewed-by: Corey Huinker, Ted Yu
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
2022-11-21 18:31:59 +09:00
Michael Paquier fb32748e32 Switch SQLValueFunction on "name" to use COERCE_SQL_SYNTAX
This commit changes six SQL keywords to use COERCE_SQL_SYNTAX rather
than relying on SQLValueFunction:
- CURRENT_ROLE
- CURRENT_USER
- USER
- SESSION_USER
- CURRENT_CATALOG
- CURRENT_SCHEMA

Among the six, "user", "current_role" and "current_catalog" require
specific SQL functions to allow ruleutils.c to map them to the SQL
keywords these require when using COERCE_SQL_SYNTAX.  Having
pg_proc.proname match with the keyword ensures that the compatibility
remains the same when projecting any of these keywords in a FROM clause
to an attribute name when an alias is not specified.  This is covered by
the tests added in 2e0d80c, making sure that a correct mapping happens
with each SQL keyword.  The three others (current_schema, session_user
and current_user) already have pg_proc entries for this job, so this
brings more consistency between the way such keywords are treated in the
parser, the executor and ruleutils.c.

SQLValueFunction is reduced to half its contents after this change,
simplifying its logic a bit as there is no need to enforce a C collation
anymore for the entries returning a name as a result.  I have made a few
performance tests, with a million-ish calls to these keywords without
seeing a difference in run-time or in perf profiles
(ExecEvalSQLValueFunction() is removed from the profiles).  The
remaining SQLValueFunctions are now related to timestamps and dates.

Bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
2022-11-20 10:58:28 +09:00
Tom Lane e9e26b5e71 Invent "multibitmapsets", and use them to speed up antijoin detection.
Implement a data structure that is a List of Bitmapsets, which is
essentially a 2-D boolean array except that the rows need not all
be the same width.  Operations such as union and intersection are
meaningful for these, just as they are for Bitmapsets.  Eventually
we might build many of the same operations that we have written for
Bitmapsets, but for the first use-case we just need a few.

That first use-case is for antijoin detection: reduce_outer_joins
needs to find the set of Vars that are certain to be non-null in a
successfully joined (not null-extended) left join row, and also
find the set of Vars subject to higher-level IS NULL constraints,
and intersect them.  We had been doing this by making Lists of
the Var nodes and then using list_intersect, which works but is
pretty inefficient compared to a bitmapset-like intersection.
Potentially it's O(N^2) if there are a lot of Vars involved,
which fortunately there generally aren't; still it's not great.
Moreover, that method requires the Vars of interest to be exactly
equal() in the join condition and the upper IS NULL condition,
which is problematic for my WIP patch that labels Vars according
to which outer joins have possibly nulled them.

Discussion: https://postgr.es/m/892228.1668437838@sss.pgh.pa.us
Discussion: https://postgr.es/m/CAMbWs4-mvPPCJ1W6iK6dD5HiNwoJdi6mZp=-7mE8N9Sh+cd0tQ@mail.gmail.com
2022-11-16 13:58:44 -05:00
Tom Lane 5e1f3b9ebf Make Bitmapsets be valid Nodes.
Add a NodeTag field to struct Bitmapset.  This is free because of
alignment considerations on 64-bit hardware.  While it adds some
space on 32-bit machines, we aren't optimizing for that case anymore.
The advantage is that data structures such as Lists of Bitmapsets
are now first-class objects to the Node infrastructure, and don't
require special-case code to handle.

This patch includes removal of one such special case, in indxpath.c:
bms_equal_any() can now be replaced by list_member().  There may be
more existing code that could be simplified, but I didn't look very
hard.  We also get to drop the read_write_ignore annotations on a
couple of RelOptInfo fields.

The outfuncs/readfuncs support is arranged so that nothing changes
in the string representation of a Bitmapset field; therefore, this
doesn't need a catversion bump.

Amit Langote and Tom Lane

Discussion: https://postgr.es/m/109089.1668197158@sss.pgh.pa.us
2022-11-13 10:22:45 -05:00
Alvaro Herrera 7fd1ae987a
Use proper macro to access TransactionId
In commit f10a025cfe I mistakenly used list_member_oid in a place
where list_member_xid is called for.  (Currently innocuous as both
typedefs are pretty much identical, but if we change either, it'll
become broken.)  Repair.

Author: Hou Zhijie <houzj.fnst@fujitsu.com>
Discussion: https://postgr.es/m/OS0PR01MB5716E2399494D4CB1A28A091942A9@OS0PR01MB5716.jpnprd01.prod.outlook.com
2022-10-20 09:41:03 +02:00
Robert Haas a448e49bcb Revert 56-bit relfilenode change and follow-up commits.
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.
2022-09-28 09:55:28 -04:00
Robert Haas 05d4cbf9b6 Increase width of RelFileNumbers from 32 bits to 56 bits.
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
2022-09-27 13:25:21 -04:00
Alvaro Herrera 249b0409b1
Fix pg_stat_statements for MERGE
We weren't jumbling the merge action list, so wildly different commands
would be considered to use the same query ID.  Add that, mention it in
the docs, and some test lines.

Backpatch to 15.

Author: Tatsu <bt22nakamorit@oss.nttdata.com>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/d87e391694db75a038abc3b2597828e8@oss.nttdata.com
2022-09-27 10:44:42 +02:00
Peter Eisentraut acd624644b Don't lose precision for float fields of Nodes.
Historically we've been more worried about making the output of
float fields look pretty than whether they'd be read back exactly.
That won't work if we're to compare the read-back nodes for
equality, so switch to using the Ryu code for float output.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
2022-09-26 16:02:09 +02:00
Peter Eisentraut 8999f5ed3c Fix write/read of empty string fields in Nodes.
Historically, outToken has represented both NULL and empty-string
strings as "<>", which readfuncs.c then read as NULL, thus failing
to preserve empty-string fields accurately.  Remarkably, this has
not caused any serious problems yet, but let's fix it.

We'll keep the "<>" notation for NULL, and use """" for empty string,
because that matches other notational choices already in use.
An actual input string of """" is converted to "\""" (this was true
already, apparently as a hangover from an ancient time when string
quoting was handled directly by pg_strtok).

CHAR fields also use "<>", but for '\0'.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
2022-09-26 15:25:59 +02:00
Peter Eisentraut a6bc330192 Add read support for some missing raw parse nodes
The node types A_Const, Constraint, and A_Expr had custom output
functions, but no read functions were implemented so far.

The A_Expr output format had to be tweaked a bit to make it easier to
parse.

Be a bit more cautious about applying strncmp to unterminated strings.

Also error out if an unrecognized enum value is found in each case,
instead of just printing a placeholder value.  That was maybe ok for
debugging but won't work if we want to have robust round-tripping.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
2022-09-24 18:18:33 -04:00
Peter Eisentraut 2cb1a5a8d4 Fix reading of BitString nodes
The node tokenizer went out of its way to store BitString node values
without the leading 'b'.  But everything else in the system stores the
leading 'b'.  This would break if a BitString node is
read-printed-read.

Also, the node tokenizer didn't know that BitString node tokens could
also start with 'x'.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
2022-09-24 18:10:52 -04:00
Peter Eisentraut 43f4b34915 Fix reading of most-negative integer value nodes
The main parser checks whether a literal fits into an int when
deciding whether it should be put into an Integer or Float node.  The
parser processes integer literals without signs.  So a most-negative
integer literal will not fit into Integer and will end up as a Float
node.

The node tokenizer did this differently.  It included the sign when
checking whether the literal fit into int.  So a most-negative integer
would indeed fit that way and end up as an Integer node.

In order to preserve the node structure correctly, we need the node
tokenizer to also analyze integer literals without sign.

There are a number of test cases in the regression tests that have a
most-negative integer argument of some utility statement, so this
issue is easily reproduced under WRITE_READ_PARSE_PLAN_TREES.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
2022-09-24 18:10:11 -04:00
Andres Freund e6927270cd meson: Add initial version of meson based build system
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
2022-09-21 22:37:17 -07:00
Tom Lane 1c27d16e6e Revise tree-walk APIs to improve spec compliance & silence warnings.
expression_tree_walker and allied functions have traditionally
declared their callback functions as, say, "bool (*walker) ()"
to allow for variation in the declared types of the callback
functions' context argument.  This is apparently going to be
forbidden by the next version of the C standard, and the latest
version of clang warns about that.  In any case it's always
been pretty poor for error-detection purposes, so fixing it is
a good thing to do.

What we want to do is change the callback argument declarations to
be like "bool (*walker) (Node *node, void *context)", which is
correct so far as expression_tree_walker and friends are concerned,
but not change the actual callback functions.  Strict compliance with
the C standard would require changing them to declare their arguments
as "void *context" and then cast to the appropriate context struct
type internally.  That'd be very invasive and it would also introduce
a bunch of opportunities for future bugs, since we'd no longer have
any check that the correct sort of context object is passed by outside
callers or internal recursion cases.  Therefore, we're just going
to ignore the standard's position that "void *" isn't necessarily
compatible with struct pointers.  No machine built in the last forty
or so years actually behaves that way, so it's not worth introducing
bug hazards for compatibility with long-dead hardware.

Therefore, to silence these compiler warnings, introduce a layer of
macro wrappers that cast the supplied function name to the official
argument type.  Thanks to our use of -Wcast-function-type, this will
still produce a warning if the supplied function is seriously
incompatible with the required signature, without going as far as
the official spec restriction does.

This method fixes the problem without any need for source code changes
outside nodeFuncs.h/.c.  However, it is an ABI break because the
physically called functions now have names ending in "_impl".  Hence
we can only fix it this way in HEAD.  In the back branches, we'll have
to settle for disabling -Wdeprecated-non-prototype.

Discussion: https://postgr.es/m/CA+hUKGKpHPDTv67Y+s6yiC8KH5OXeDg6a-twWo_xznKTcG0kSA@mail.gmail.com
2022-09-20 18:03:22 -04:00
Andrew Dunstan 2f2b18bd3f Revert SQL/JSON features
The reverts the following and makes some associated cleanups:

    commit f79b803dc: Common SQL/JSON clauses
    commit f4fb45d15: SQL/JSON constructors
    commit 5f0adec25: Make STRING an unreserved_keyword.
    commit 33a377608: IS JSON predicate
    commit 1a36bc9db: SQL/JSON query functions
    commit 606948b05: SQL JSON functions
    commit 49082c2cc: RETURNING clause for JSON() and JSON_SCALAR()
    commit 4e34747c8: JSON_TABLE
    commit fadb48b00: PLAN clauses for JSON_TABLE
    commit 2ef6f11b0: Reduce running time of jsonb_sqljson test
    commit 14d3f24fa: Further improve jsonb_sqljson parallel test
    commit a6baa4bad: Documentation for SQL/JSON features
    commit b46bcf7a4: Improve readability of SQL/JSON documentation.
    commit 112fdb352: Fix finalization for json_objectagg and friends
    commit fcdb35c32: Fix transformJsonBehavior
    commit 4cd8717af: Improve a couple of sql/json error messages
    commit f7a605f63: Small cleanups in SQL/JSON code
    commit 9c3d25e17: Fix JSON_OBJECTAGG uniquefying bug
    commit a79153b7a: Claim SQL standard compliance for SQL/JSON features
    commit a1e7616d6: Rework SQL/JSON documentation
    commit 8d9f9634e: Fix errors in copyfuncs/equalfuncs support for JSON node types.
    commit 3c633f32b: Only allow returning string types or bytea from json_serialize
    commit 67b26703b: expression eval: Fix EEOP_JSON_CONSTRUCTOR and EEOP_JSONEXPR size.

The release notes are also adjusted.

Backpatch to release 15.

Discussion: https://postgr.es/m/40d2c882-bcac-19a9-754d-4299e1d87ac7@postgresql.org
2022-09-01 17:07:14 -04:00
Peter Eisentraut 1c5818b9c6 Remove redundant spaces in _outA_Expr() output
Since WRITE_NODE_FIELD() output always starts with a space, we don't
need to go out of our way to print another space right before it.

This change is only for visual appearance; the tokenizer on the
reading side would read it the same way (but there is no read support
for A_Expr at this time anyway).
2022-08-15 12:43:52 +02:00
Peter Eisentraut abf46ad9c7 Add missing fields to _outConstraint()
As of 897795240c, check constraints can
be declared invalid.  But that patch didn't update _outConstraint() to
also show the relevant struct fields (which were only applicable to
foreign keys before that).  This currently only affects debugging
output, so no impact in practice.
2022-08-13 10:32:38 +02:00
Peter Eisentraut e7a552f303 Fix _outConstraint() for "identity" constraints
The set of fields printed by _outConstraint() in the CONSTR_IDENTITY
case didn't match the set of fields actually used in that case.  (The
code was probably uncarefully copied from the CONSTR_DEFAULT case.)
Fix that by using the right set of fields.  Since there is no read
support for this node type, this is really just for debugging output
right now, so it doesn't affect anything important.
2022-08-12 08:17:30 +02:00
Peter Eisentraut 4e6dcbb6ae Add missing space in _outA_Const() output
Mistake introduced by 639a86e36a.
2022-08-11 10:35:56 +02:00
Tom Lane 9a9f25e217 Fix MSVC build script's check for obsolete node support functions.
Commit 964d01ae9 was a few bricks shy of a load here: the script
checked whether gen_node_support.pl itself had been updated since it
was last run, but not whether any of its input files had been updated.
Fix that.  While here, scrape the list of input files from the
Makefiles rather than having a duplicate copy, as we do for most
other lists of source files.

In passing, improve gen_node_support.pl's error report for an
incorrect file list.

Per gripe from Amit Kapila.

Discussion: https://postgr.es/m/CAA4eK1KQk4vP-3mTAz26h-PRUZaGu8Fc=q-ZKSajsAthH0A15w@mail.gmail.com
2022-08-08 14:43:35 -04:00
Tom Lane 1aa8dad41f Fix incorrect tests for SRFs in relation_can_be_sorted_early().
Commit fac1b470a thought we could check for set-returning functions
by testing only the top-level node in an expression tree.  This is
wrong in itself, and to make matters worse it encouraged others
to make the same mistake, by exporting tlist.c's special-purpose
IS_SRF_CALL() as a widely-visible macro.  I can't find any evidence
that anyone's taken the bait, but it was only a matter of time.

Use expression_returns_set() instead, and stuff the IS_SRF_CALL()
genie back in its bottle, this time with a warning label.  I also
added a couple of cross-reference comments.

After a fair amount of fooling around, I've despaired of making
a robust test case that exposes the bug reliably, so no test case
here.  (Note that the test case added by fac1b470a is itself
broken, in that it doesn't notice if you remove the code change.
The repro given by the bug submitter currently doesn't fail either
in v15 or HEAD, though I suspect that may indicate an unrelated bug.)

Per bug #17564 from Martijn van Oosterhout.  Back-patch to v13,
as the faulty patch was.

Discussion: https://postgr.es/m/17564-c7472c2f90ef2da3@postgresql.org
2022-08-03 17:33:42 -04:00
Tom Lane af119e08fd Dump more fields when dumping planner internal data structures.
Commit 964d01ae9 marked a lot of fields as read_write_ignore
to stay consistent with what was dumped by the manually-maintained
outfuncs.c code.  However, it seems that a pretty fair number
of those omissions were either flat-out oversights, or a shortcut
taken because hand-written code seemed like it'd be too much trouble.
Let's upgrade things where it seems to make sense to dump.

To do this, we need to add support to gen_node_support.pl and
outfuncs.c for variable-length arrays of Node pointers.  That's
pretty straightforward given the model of the existing code
for arrays of scalars, but I found I needed to tighten the
type-recognizing regexes in gen_node_support.pl.  (As they
stood, they mistook "foo **" for "foo *".  Make sure they're
all fully anchored to prevent additional problems.)

The main thing left un-done here is that a lot of partitioning-related
structs are still not dumped, because they are bare structs not Nodes.
I'm not sure about the wisdom of that choice ... but changing it would
be fairly invasive, so it probably requires more justification than
just making planner node dumps more complete.

Discussion: https://postgr.es/m/1295668.1658258637@sss.pgh.pa.us
2022-07-20 13:54:30 -04:00
Tom Lane 2d04277121 Make serialization of Nodes' scalar-array fields more robust.
When the ability to print variable-length-array fields was first
added to outfuncs.c, there was no corresponding read capability,
as it was used only for debug dumps of planner-internal Nodes.
Not a lot of thought seems to have been put into the output format:
it's just the space-separated array elements and nothing else.
Later such fields appeared in Plan nodes, and still later we grew
read support so that Plans could be transferred to parallel workers,
but the original text format wasn't rethought.  It seems inadequate
to me because (a) no cross-check is possible that we got the right
number of array entries, (b) we can't tell the difference between
a NULL pointer and a zero-length array, and (c) except for
WRITE_INDEX_ARRAY, we'd crash if a non-zero length is specified
when the pointer is NULL, a situation that can arise in some fields
that we currently conveniently avoid printing.

Since we're currently in a campaign to make the Node infrastructure
generally more it-just-works-without-thinking-about-it, now seems
like a good time to improve this.

Let's adopt a format similar to that used for Lists, that is "<>"
for a NULL pointer or "(item item item)" otherwise.  Also retool
the code to not have so many copies of the identical logic.

I bumped catversion out of an abundance of caution, although I think
that we don't use any such array fields in Nodes that can get into
the catalogs.

Discussion: https://postgr.es/m/1528424.1658272135@sss.pgh.pa.us
2022-07-20 13:04:33 -04:00
Andres Freund adba4b7471 Add output directory option to gen_node_support.pl
This is in preparation for building postgres with meson / ninja.

When building with meson, commands are run at the root of the build tree. Add
an option to put build output into the appropriate place. This can be utilized
by src/tools/msvc/ for a minor simplification, which also provides some
coverage for the new option.

Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/5e216522-ba3c-f0e6-7f97-5276d0270029@enterprisedb.com
2022-07-18 12:32:53 -07:00
Tom Lane 7c0eb3c622 Tighten up parsing logic in gen_node_support.pl.
Teach this script to handle function pointer fields honestly.
Previously they were just silently ignored, but that's not likely to
be a behavior we can accept indefinitely.  This mostly entails fixing
it so that a field declaration spanning multiple lines can be parsed,
because we have a bunch of such fields that're laid out that way.
But that's a good improvement in its own right.

With that change and a minor regex adjustment, the only struct it
fails to parse in the node-defining headers is A_Const, because
of the embedded union.  The path of least resistance is to move
that union declaration outside the struct.

Having done those things, we can make it error out if it finds
any within-struct syntax it doesn't understand, which seems like
a pretty important property for robustness.

This commit doesn't change the output files at all; it's just in
the way of future-proofing.

Discussion: https://postgr.es/m/2593369.1657759779@sss.pgh.pa.us
2022-07-14 09:04:23 -04:00
Tom Lane ff33a8c887 Remove artificial restrictions on which node types have out/read funcs.
The initial version of gen_node_support.pl manually excluded most
utility statement node types from having out/read support, and
also some raw-parse-tree-only node types.  That was mostly to keep
the output comparable to the old hand-maintained code.  We'd like
to have out/read support for utility statements, for debugging
purposes and so that they can be included in new-style SQL functions;
so it's time to lift that restriction.

Most if not all of the previously-excluded raw-parse-tree-only node
types can appear in expression subtrees of utility statements, so
they have to be handled too.

We don't quite have full read support yet; certain custom_read_write
node types need to have their handwritten read functions implemented
before that will work.

Doing this allows us to drop the previous hack in _outQuery to not
dump the utilityStmt field in most cases, which means we no longer
need manually-maintained out/read functions for Query, so get rid
of those in favor of auto-generating them.

Fix a couple of omissions in gen_node_support.pl that are exposed
through having to handle more node types.

catversion bump forced because somebody was sloppy about the field
order in the manually-maintained Query out/read functions.
(Committers should note that almost all changes in parsenodes.h
are now grounds for a catversion bump.)
2022-07-13 11:48:17 -04:00
Alvaro Herrera 7057bf2354
Fix XID list support some more
Read/out support in 5ca0fe5c8a was missing/incomplete, per Tom Lane.
Again, as far as core is concerned, this is not only dead code but also
untested; however, third parties may come to rely on it, so the standard
features should work.

Discussion: https://postgr.es/m/1548311.1657636605@sss.pgh.pa.us
2022-07-13 10:34:54 +02:00
David Rowley 4cc832f94a Tidy up code in get_cheapest_group_keys_order()
There are a few things that we could do a little better within
get_cheapest_group_keys_order():

1. We should be using list_free() rather than pfree() on a List.

2. We should use for_each_from() instead of manually coding a for loop to
skip the first n elements of a List

3. list_truncate(list_copy(...), n) is not a great way to copy the first n
elements of a list. Let's invent list_copy_head() for that.  That way we
don't need to copy the entire list just to truncate it directly
afterwards.

4. We can simplify finding the cheapest cost by setting the cheapest cost
variable to DBL_MAX.  That allows us to skip special-casing the initial
iteration of the loop.

Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvrGyL3ft8waEkncG9y5HDMu5TFFJB1paoTC8zi9YK97Nw@mail.gmail.com
Backpatch-through: 15, where get_cheapest_group_keys_order was added.
2022-07-13 14:02:20 +12:00
Tom Lane eea9fa9b25 Add defenses against unexpected changes in the NodeTag enum list.
Having different build systems producing different contents of the
NodeTag enum would be catastrophic for extension ABI stability.
But that ordering depends on the order in which gen_node_support.pl
processes its input files.  It seems too fragile to let the Makefiles,
MSVC build scripts, and soon meson build scripts all set this order
independently.  As a klugy but serviceable solution, put a canonical
copy of the file list into gen_node_support.pl itself, and check that
against the files given on the command line.

Also, while it's fine to add and delete node tags during development,
we must not let the assigned NodeTag values change unexpectedly in
stable branches.  Add a cross-check that can be enabled when a branch
is forked off (or later, but that is a time when we're unlikely to
miss doing it).  It just checks that the last auto-assigned number
doesn't change, which is simplistic but will catch the most likely
sorts of mistakes.

From time to time we do need to add a node tag in a stable branch.
To support doing that without changing the branch's auto-assigned
tag numbers, invent pg_node_attr(nodetag_number(VALUE)) which can
be used to give such a node a hand-assigned tag above the last
auto-assigned one.

Discussion: https://postgr.es/m/1249010.1657574337@sss.pgh.pa.us
2022-07-12 11:22:52 -04:00
Tom Lane ca187d7455 Invent nodetag_only attribute for Nodes.
This allows explaining gen_node_support.pl's handling of execnodes.h
and some other input files as being a shortcut for explicit marking
of all their node declarations as pg_node_attr(nodetag_only).
I foresee that someday we might need to be more fine-grained about
that, and this change provides the infrastructure needed to do so.
For now, it just allows removal of the script's klugy special case
for CallContext and InlineCodeBlock.

Discussion: https://postgr.es/m/75063.1657410615@sss.pgh.pa.us
2022-07-12 10:46:58 -04:00