Commit Graph

2215 Commits

Author SHA1 Message Date
Peter Eisentraut 665d1fad99 Logical replication
- Add PUBLICATION catalogs and DDL
- Add SUBSCRIPTION catalog and DDL
- Define logical replication protocol and output plugin
- Add logical replication workers

From: Petr Jelinek <petr@2ndquadrant.com>
Reviewed-by: Steve Singer <steve@ssinger.info>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Erik Rijkers <er@xs4all.nl>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
2017-01-20 09:04:49 -05:00
Alvaro Herrera 9a34123bc3 Make messages mentioning type names more uniform
This avoids additional translatable strings for each distinct type, as
well as making our quoting style around type names more consistent
(namely, that we don't quote type names).  This continues what started
as f402b99501.

Discussion: https://postgr.es/m/20160401170642.GA57509@alvherre.pgsql
2017-01-18 16:08:20 -03:00
Tom Lane d43a619c60 Fix check_srf_call_placement() to handle VALUES cases correctly.
INSERT ... VALUES with a single VALUES row is implemented quite differently
from the general VALUES case.  A user-visible implication of that is that
we accept SRFs in the single-row case, but not in the multi-row case.
That's a historical artifact no doubt, but in view of the lack of field
complaints, I'm not excited about fixing it right now.

However, check_srf_call_placement() needs to know about this, first because
it should throw an error in the unsupported case, and second because it
should set p_hasTargetSRFs in the single-row case (because we treat that
like a SELECT tlist).  That's an oversight in commit a4c35ea1c.

To fix, split EXPR_KIND_VALUES into two values.  So far as I can see,
this is the only place where we need to distinguish the two cases at
present; but there might be more later.

Patch by me, per report from Andres Freund.

Discussion: https://postgr.es/m/20170116081548.zg63zltblwimpfgp@alap3.anarazel.de
2017-01-16 15:23:11 -05:00
Tom Lane ab1f0c8225 Change representation of statement lists, and add statement location info.
This patch makes several changes that improve the consistency of
representation of lists of statements.  It's always been the case
that the output of parse analysis is a list of Query nodes, whatever
the types of the individual statements in the list.  This patch brings
similar consistency to the outputs of raw parsing and planning steps:

* The output of raw parsing is now always a list of RawStmt nodes;
the statement-type-dependent nodes are one level down from that.

* The output of pg_plan_queries() is now always a list of PlannedStmt
nodes, even for utility statements.  In the case of a utility statement,
"planning" just consists of wrapping a CMD_UTILITY PlannedStmt around
the utility node.  This list representation is now used in Portal and
CachedPlan plan lists, replacing the former convention of intermixing
PlannedStmts with bare utility-statement nodes.

Now, every list of statements has a consistent head-node type depending
on how far along it is in processing.  This allows changing many places
that formerly used generic "Node *" pointers to use a more specific
pointer type, thus reducing the number of IsA() tests and casts needed,
as well as improving code clarity.

Also, the post-parse-analysis representation of DECLARE CURSOR is changed
so that it looks more like EXPLAIN, PREPARE, etc.  That is, the contained
SELECT remains a child of the DeclareCursorStmt rather than getting flipped
around to be the other way.  It's now true for both Query and PlannedStmt
that utilityStmt is non-null if and only if commandType is CMD_UTILITY.
That allows simplifying a lot of places that were testing both fields.
(I think some of those were just defensive programming, but in many places,
it was actually necessary to avoid confusing DECLARE CURSOR with SELECT.)

Because PlannedStmt carries a canSetTag field, we're also able to get rid
of some ad-hoc rules about how to reconstruct canSetTag for a bare utility
statement; specifically, the assumption that a utility is canSetTag if and
only if it's the only one in its list.  While I see no near-term need for
relaxing that restriction, it's nice to get rid of the ad-hocery.

The API of ProcessUtility() is changed so that what it's passed is the
wrapper PlannedStmt not just the bare utility statement.  This will affect
all users of ProcessUtility_hook, but the changes are pretty trivial; see
the affected contrib modules for examples of the minimum change needed.
(Most compilers should give pointer-type-mismatch warnings for uncorrected
code.)

There's also a change in the API of ExplainOneQuery_hook, to pass through
cursorOptions instead of expecting hook functions to know what to pick.
This is needed because of the DECLARE CURSOR changes, but really should
have been done in 9.6; it's unlikely that any extant hook functions
know about using CURSOR_OPT_PARALLEL_OK.

Finally, teach gram.y to save statement boundary locations in RawStmt
nodes, and pass those through to Query and PlannedStmt nodes.  This allows
more intelligent handling of cases where a source query string contains
multiple statements.  This patch doesn't actually do anything with the
information, but a follow-on patch will.  (Passing this information through
cleanly is the true motivation for these changes; while I think this is all
good cleanup, it's unlikely we'd have bothered without this end goal.)

catversion bump because addition of location fields to struct Query
affects stored rules.

This patch is by me, but it owes a good deal to Fabien Coelho who did
a lot of preliminary work on the problem, and also reviewed the patch.

Discussion: https://postgr.es/m/alpine.DEB.2.20.1612200926310.29821@lancre
2017-01-14 16:02:35 -05:00
Tom Lane 7c3abe3c92 Get rid of ParseState.p_value_substitute; use a columnref hook instead.
I noticed that p_value_substitute, which is a single-purpose kluge I added
in 2002 (commit b0422b215), could be replaced by having domainAddConstraint
install a parser hook that looks for the name "value".  The parser hook
code only dates back to 2009, so it's not surprising that we had to kluge
this in 2002, but we can do it more cleanly now.
2017-01-07 16:02:16 -05:00
Bruce Momjian 1d25779284 Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
Peter Eisentraut 2e254130d1 Make more use of RoleSpec struct
Most code was casting this through a generic Node.  By declaring
everything as RoleSpec appropriately, we can remove a bunch of casts and
ad-hoc node type checking.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
2016-12-29 10:49:39 -05:00
Tom Lane fe591f8bf6 Replace enum InhOption with simple boolean.
Now that it has only INH_NO and INH_YES values, it's just weird that
it's not a plain bool, so make it that way.

Also rename RangeVar.inhOpt to "inh", to be like RangeTblEntry.inh.
My recollection is that we gave it a different name specifically because
it had a different representation than the derived bool value, but it
no longer does.  And this is a good forcing function to be sure we
catch any places that are affected by the change.

Bump catversion because of possible effect on stored RangeVar nodes.
I'm not exactly convinced that we ever store RangeVar on disk, but
we have a readfuncs function for it, so be cautious.  (If we do do so,
then commit e13486eba was in error not to bump catversion.)

Follow-on to commit e13486eba.

Discussion: http://postgr.es/m/CA+TgmoYe+EG7LdYX6pkcNxr4ygkP4+A=jm9o-CPXyOvRiCNwaQ@mail.gmail.com
2016-12-23 13:35:18 -05:00
Robert Haas e13486eba0 Remove sql_inheritance GUC.
This backward-compatibility GUC is long overdue for removal.

Discussion: http://postgr.es/m/CA+TgmoYe+EG7LdYX6pkcNxr4ygkP4+A=jm9o-CPXyOvRiCNwaQ@mail.gmail.com
2016-12-23 07:35:01 -05:00
Tom Lane 1ead0208b2 Fix CREATE TABLE ... LIKE ... WITH OIDS.
Having a WITH OIDS specification should result in the creation of an OID
column, but commit b943f502b broke that in the case that there were LIKE
tables without OIDS.  Commentary in that patch makes it look like this was
intentional, but if so it was based on a faulty reading of what inheritance
does: the parent tables can add an OID column, but they can't subtract one.
AFAICS, the behavior ought to be that you get an OID column if any of the
inherited tables, LIKE tables, or WITH clause ask for one.

Also, revert that patch's unnecessary split of transformCreateStmt's loop
over the tableElts list into two passes.  That seems to have been based on
a misunderstanding as well: we already have two-pass processing here,
we don't need three passes.

Per bug #14474 from Jeff Dafoe.  Back-patch to 9.6 where the misbehavior
was introduced.

Report: https://postgr.es/m/20161222145304.25620.47445@wrigleys.postgresql.org
2016-12-22 16:23:38 -05:00
Tom Lane a8ae12322a Fix detection of unfinished Unicode surrogate pair at end of string.
The U&'...' and U&"..." syntaxes silently discarded a surrogate pair
start (that is, a code between U+D800 and U+DBFF) if it occurred at
the very end of the string.  This seems like an obvious oversight,
since we throw an error for every other invalid combination of surrogate
characters, including the very same situation in E'...' syntax.

This has been wrong since the pair processing was added (in 9.0),
so back-patch to all supported branches.

Discussion: https://postgr.es/m/19113.1482337898@sss.pgh.pa.us
2016-12-21 17:39:32 -05:00
Tom Lane 0b78106cd4 Fix reporting of column typmods for multi-row VALUES constructs.
expandRTE() and get_rte_attribute_type() reported the exprType() and
exprTypmod() values of the expressions in the first row of the VALUES as
being the column type/typmod returned by the VALUES RTE.  That's fine for
the data type, since we coerce all expressions in a column to have the same
common type.  But we don't coerce them to have a common typmod, so it was
possible for rows after the first one to return values that violate the
claimed column typmod.  This leads to the incorrect result seen in bug
#14448 from Hassan Mahmood, as well as some other corner-case misbehaviors.

The desired behavior is the same as we use in other type-unification
cases: report the common typmod if there is one, but otherwise return -1
indicating no particular constraint.  It's cheap for transformValuesClause
to determine the common typmod while transforming a multi-row VALUES, but
it'd be less cheap for expandRTE() and get_rte_attribute_type() to
re-determine that info every time they're asked --- possibly a lot less
cheap, if the VALUES has many rows.  Therefore, the best fix is to record
the common typmods explicitly in a list in the VALUES RTE, as we were
already doing for column collations.  This looks quite a bit like what
we're doing for CTE RTEs, so we can save a little bit of space and code by
unifying the representation for those two RTE types.  They both now share
coltypes/coltypmods/colcollations fields.  (At some point it might seem
desirable to populate those fields for all RTE types; but right now it
looks like constructing them for other RTE types would add more code and
cycles than it would save.)

The RTE change requires a catversion bump, so this fix is only usable
in HEAD.  If we fix this at all in the back branches, the patch will
need to look quite different.

Report: https://postgr.es/m/20161205143037.4377.60754@wrigleys.postgresql.org
Discussion: https://postgr.es/m/27429.1480968538@sss.pgh.pa.us
2016-12-08 11:40:02 -05:00
Robert Haas f0e44751d7 Implement table partitioning.
Table partitioning is like table inheritance and reuses much of the
existing infrastructure, but there are some important differences.
The parent is called a partitioned table and is always empty; it may
not have indexes or non-inherited constraints, since those make no
sense for a relation with no data of its own.  The children are called
partitions and contain all of the actual data.  Each partition has an
implicit partitioning constraint.  Multiple inheritance is not
allowed, and partitioning and inheritance can't be mixed.  Partitions
can't have extra columns and may not allow nulls unless the parent
does.  Tuples inserted into the parent are automatically routed to the
correct partition, so tuple-routing ON INSERT triggers are not needed.
Tuple routing isn't yet supported for partitions which are foreign
tables, and it doesn't handle updates that cross partition boundaries.

Currently, tables can be range-partitioned or list-partitioned.  List
partitioning is limited to a single column, but range partitioning can
involve multiple columns.  A partitioning "column" can be an
expression.

Because table partitioning is less general than table inheritance, it
is hoped that it will be easier to reason about properties of
partitions, and therefore that this will serve as a better foundation
for a variety of possible optimizations, including query planner
optimizations.  The tuple routing based which this patch does based on
the implicit partitioning constraints is an example of this, but it
seems likely that many other useful optimizations are also possible.

Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat,
Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova,
Rushabh Lathia, Erik Rijkers, among others.  Minor revisions by me.
2016-12-07 13:17:55 -05:00
Stephen Frost 093129c9d9 Add support for restrictive RLS policies
We have had support for restrictive RLS policies since 9.5, but they
were only available through extensions which use the appropriate hooks.
This adds support into the grammer, catalog, psql and pg_dump for
restrictive RLS policies, thus reducing the cases where an extension is
necessary.

In passing, also move away from using "AND"d and "OR"d in comments.
As pointed out by Alvaro, it's not really appropriate to attempt
to make verbs out of "AND" and "OR", so reword those comments which
attempted to.

Reviewed By: Jeevan Chalke, Dean Rasheed
Discussion: https://postgr.es/m/20160901063404.GY4028@tamriel.snowman.net
2016-12-05 15:50:55 -05:00
Tom Lane 3850723208 Don't mess up pstate->p_next_resno in transformOnConflictClause().
transformOnConflictClause incremented p_next_resno while generating the
phony targetlist for the EXCLUDED pseudo-rel.  Then that field got
incremented some more during transformTargetList, possibly leading to
free_parsestate concluding that we'd overrun the allowed length of a tlist,
as reported by Justin Pryzby.

We could fix this by resetting p_next_resno to 1 after using it for the
EXCLUDED pseudo-rel tlist, but it seems easier and less coupled to other
places if we just don't use that field at all in this loop.  (Note that
this doesn't change anything about the resnos that end up appearing in
the main target list, because those are all replaced with target-column
numbers by updateTargetListEntry.)

In passing, fix incorrect type OID assigned to the whole-row Var for
"EXCLUDED.*" (somehow this escaped having any bad consequences so far,
but it's certainly wrong); remove useless assignment to var->location;
pstrdup the column names in case of a relcache flush; and improve
nearby comments.

Back-patch to 9.5 where ON CONFLICT was introduced.

Report: https://postgr.es/m/20161204163237.GA8030@telsasoft.com
2016-12-04 15:02:45 -05:00
Peter Eisentraut b999c247a5 Add aggregate_with_argtypes and use it consistently
This works like function_with_argtypes, but aggregates allow slightly
different arguments.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2016-12-01 17:38:49 -05:00
Peter Eisentraut e696dccec1 Move function_with_argtypes to a better location
It was apparently added for use by GRANT/REVOKE, but move it closer to
where other function signature related things are kept.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2016-12-01 17:38:44 -05:00
Peter Eisentraut 0aff9293bf Use grammar symbol function_with_argtypes consistently
Instead of sometimes referring to a function signature like func_name
func_args, use the existing function_with_argtypes symbol, which
combines the two.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2016-12-01 17:37:42 -05:00
Tom Lane 906bfcad7b Improve handling of "UPDATE ... SET (column_list) = row_constructor".
Previously, the right-hand side of a multiple-column assignment, if it
wasn't a sub-SELECT, had to be a simple parenthesized expression list,
because gram.y was responsible for "bursting" the construct into
independent column assignments.  This had the minor defect that you
couldn't write ROW (though you should be able to, since the standard says
this is a row constructor), and the rather larger defect that unlike other
uses of row constructors, we would not expand a "foo.*" item into multiple
columns.

Fix that by changing the RHS to be just "a_expr" in the grammar, leaving
it to transformMultiAssignRef to separate the elements of a RowExpr;
which it will do only after performing standard transformation of the
RowExpr, so that "foo.*" behaves as expected.

The key reason we didn't do that before was the hard-wired handling of
DEFAULT tokens (SetToDefault nodes).  This patch deals with that issue by
allowing DEFAULT in any a_expr and having parse analysis throw an error
if SetToDefault is found in an unexpected place.  That's an improvement
anyway since the error can be more specific than just "syntax error".

The SQL standard suggests that the RHS could be any a_expr yielding a
suitable row value.  This patch doesn't really move the goal posts in that
respect --- you're still limited to RowExpr or a sub-SELECT --- but it does
fix the grammar restriction, so it provides some tangible progress towards
a full implementation.  And the limitation is now documented by an explicit
error message rather than an unhelpful "syntax error".

Discussion: <8542.1479742008@sss.pgh.pa.us>
2016-11-22 15:20:10 -05:00
Tom Lane c5f365f3ab Prevent multicolumn expansion of "foo.*" in an UPDATE source expression.
Because we use transformTargetList() for UPDATE as well as SELECT
tlists, the code accidentally tried to expand a "*" reference into
several columns.  This is nonsensical, because the UPDATE syntax
provides exactly one target column to put the value into.  The
immediate result was that transformUpdateTargetList() got confused
and reported "UPDATE target count mismatch --- internal error".
It seems better to treat such a reference as a plain whole-row
variable, as it would be in other contexts.  (This could produce
useful results when the target column is of composite type.)

Fix by tweaking transformTargetList() to perform *-expansion only
conditionally, depending on its exprKind parameter.

Back-patch to 9.3.  The problem exists further back, but a fix would be
much more invasive before that, because transformTargetList() wasn't
told what kind of list it was working on.  Doesn't seem worth the
trouble given the lack of field reports.  (I only noticed it because
I was checking the code while trying to improve the documentation about
how we handle "foo.*".)

Discussion: <4308.1479595330@sss.pgh.pa.us>
2016-11-20 14:26:19 -05:00
Kevin Grittner 8c48375e5f Implement syntax for transition tables in AFTER triggers.
This is infrastructure for the complete SQL standard feature.  No
support is included at this point for execution nodes or PLs.  The
intent is to add that soon.

As this patch leaves things, standard syntax can create tuplestores
to contain old and/or new versions of rows affected by a statement.
References to these tuplestores are in the TriggerData structure.
C triggers can access the tuplestores directly, so they are usable,
but they cannot yet be referenced within a SQL statement.
2016-11-04 10:49:50 -05:00
Tom Lane e8bdee2770 Add ALTER EXTENSION ADD/DROP ACCESS METHOD, and use it in pg_upgrade.
Without this, an extension containing an access method is not properly
dumped/restored during pg_upgrade --- the AM ends up not being a member
of the extension after upgrading.

Another oversight in commit 473b93287, reported by Andrew Dunstan.

Report: <f7ac29f3-515c-2a44-21c5-ec925053265f@dunslane.net>
2016-10-02 14:31:28 -04:00
Bruce Momjian 1ff0042165 C comment: fix function header comment
Fix for transformOnConflictClause().

Author: Tomonari Katsumata
2016-09-22 17:34:24 -04:00
Tom Lane a4c35ea1c2 Improve parser's and planner's handling of set-returning functions.
Teach the parser to reject misplaced set-returning functions during parse
analysis using p_expr_kind, in much the same way as we do for aggregates
and window functions (cf commit eaccfded9).  While this isn't complete
(it misses nesting-based restrictions), it's much better than the previous
error reporting for such cases, and it allows elimination of assorted
ad-hoc expression_returns_set() error checks.  We could add nesting checks
later if it seems important to catch all cases at parse time.

There is one case the parser will now throw error for although previous
versions allowed it, which is SRFs in the tlist of an UPDATE.  That never
behaved sensibly (since it's ill-defined which generated row should be
used to perform the update) and it's hard to see why it should not be
treated as an error.  It's a release-note-worthy change though.

Also, add a new Query field hasTargetSRFs reporting whether there are
any SRFs in the targetlist (including GROUP BY/ORDER BY expressions).
The parser can now set that basically for free during parse analysis,
and we can use it in a number of places to avoid expression_returns_set
searches.  (There will be more such checks soon.)  In some places, this
allows decontorting the logic since it's no longer expensive to check for
SRFs in the tlist --- so I made the checks parallel to the handling of
hasAggs/hasWindowFuncs wherever it seemed appropriate.

catversion bump because adding a Query field changes stored rules.

Andres Freund and Tom Lane

Discussion: <24639.1473782855@sss.pgh.pa.us>
2016-09-13 13:54:24 -04:00
Tom Lane 0ab9c56d0f Support renaming an existing value of an enum type.
Not much to be said about this patch: it does what it says on the tin.

In passing, rename AlterEnumStmt.skipIfExists to skipIfNewValExists
to clarify what it actually does.  In the discussion of this patch
we considered supporting other similar options, such as IF EXISTS
on the type as a whole or IF NOT EXISTS on the target name.  This
patch doesn't actually add any such feature, but it might happen later.

Dagfinn Ilmari Mannsåker, reviewed by Emre Hasegeli

Discussion: <CAO=2mx6uvgPaPDf-rHqG8=1MZnGyVDMQeh8zS4euRyyg4D35OQ@mail.gmail.com>
2016-09-07 16:11:56 -04:00
Peter Eisentraut 49eb0fd097 Add location field to DefElem
Add a location field to the DefElem struct, used to parse many utility
commands.  Update various error messages to supply error position
information.

To propogate the error position information in a more systematic way,
create a ParseState in standard_ProcessUtility() and pass that to
interested functions implementing the utility commands.  This seems
better than passing the query string and then reassembling a parse state
ad hoc, which violates the encapsulation of the ParseState type.

Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
2016-09-06 12:00:00 -04:00
Tom Lane 0bb51aa967 Improve parsetree representation of special functions such as CURRENT_DATE.
We implement a dozen or so parameterless functions that the SQL standard
defines special syntax for.  Up to now, that was done by converting them
into more or less ad-hoc constructs such as "'now'::text::date".  That's
messy for multiple reasons: it exposes what should be implementation
details to users, and performance is worse than it needs to be in several
cases.  To improve matters, invent a new expression node type
SQLValueFunction that can represent any of these parameterless functions.

Bump catversion because this changes stored parsetrees for rules.

Discussion: <30058.1463091294@sss.pgh.pa.us>
2016-08-16 20:33:01 -04:00
Tom Lane 4997878193 Doc: clarify that DROP ... CASCADE is recursive.
Apparently that's not obvious to everybody, so let's belabor the point.

In passing, document that DROP POLICY has CASCADE/RESTRICT options (which
it does, per gram.y) but they do nothing (I assume, anyway).  Also update
some long-obsolete commentary in gram.y.

Discussion: <20160805104837.1412.84915@wrigleys.postgresql.org>
2016-08-12 18:45:18 -04:00
Tom Lane a3c7a993d5 Make INSERT-from-multiple-VALUES-rows handle targetlist indirection better.
Previously, if an INSERT with multiple rows of VALUES had indirection
(array subscripting or field selection) in its target-columns list, the
parser handled that by applying transformAssignedExpr() to each element
of each VALUES row independently.  This led to having ArrayRef assignment
nodes or FieldStore nodes in each row of the VALUES RTE.  That works for
simple cases, but in bug #14265 Nuri Boardman points out that it fails
if there are multiple assignments to elements/fields of the same target
column.  For such cases to work, rewriteTargetListIU() has to nest the
ArrayRefs or FieldStores together to produce a single expression to be
assigned to the column.  But it failed to find them in the top-level
targetlist and issued an error about "multiple assignments to same column".

We could possibly fix this by teaching the rewriter to apply
rewriteTargetListIU to each VALUES row separately, but that would be messy
(it would change the output rowtype of the VALUES RTE, for example) and
inefficient.  Instead, let's fix the parser so that the VALUES RTE outputs
are just the user-specified values, cast to the right type if necessary,
and then the ArrayRefs or FieldStores are applied in the top-level
targetlist to Vars representing the RTE's outputs.  This is the same
parsetree representation already used for similar cases with INSERT/SELECT
syntax, so it allows simplifications in ruleutils.c, which no longer needs
to treat INSERT-from-multiple-VALUES as its own special case.

This implementation works by applying transformAssignedExpr to the VALUES
entries as before, and then stripping off any ArrayRefs or FieldStores it
adds.  With lots of VALUES rows it would be noticeably more efficient to
not add those nodes in the first place.  But that's just an optimization
not a bug fix, and there doesn't seem to be any good way to do it without
significant refactoring.  (A non-invasive answer would be to apply
transformAssignedExpr + stripping to just the first VALUES row, and then
just forcibly cast remaining rows to the same data types exposed in the
first row.  But this way would lead to different, not-INSERT-specific
errors being reported in casting failure cases, so it doesn't seem very
nice.)  So leave that for later; this patch at least isn't making the
per-row parsing work worse, and it does make the finished parsetree
smaller, saving rewriter and planner work.

Catversion bump because stored rules containing such INSERTs would need
to change.  Because of that, no back-patch, even though this is a very
long-standing bug.

Report: <20160727005725.7438.26021@wrigleys.postgresql.org>
Discussion: <9578.1469645245@sss.pgh.pa.us>
2016-08-03 16:37:03 -04:00
Tom Lane 8d19d0e139 Teach parser to transform "x IS [NOT] DISTINCT FROM NULL" to a NullTest.
Now that we've nailed down the principle that NullTest with !argisrow
is fully equivalent to SQL's IS [NOT] DISTINCT FROM NULL, let's teach
the parser about it.  This produces a slightly more compact parse tree
and is much more amenable to optimization than a DistinctExpr, since
the planner knows a good deal about NullTest and next to nothing about
DistinctExpr.

I'm not sure that there are all that many queries in the wild that could
be improved by this, but at least one source of such cases is the patch
just made to postgres_fdw to emit IS [NOT] DISTINCT FROM NULL when
IS [NOT] NULL isn't semantically correct.

No back-patch, since to the extent that this does affect planning results,
it might be considered undesirable plan destabilization.
2016-07-28 17:23:13 -04:00
Tom Lane 46b773d4fe Improve documentation about CREATE TABLE ... LIKE.
The docs failed to explain that LIKE INCLUDING INDEXES would not preserve
the names of indexes and associated constraints.  Also, it wasn't mentioned
that EXCLUDE constraints would be copied by this option.  The latter
oversight seems enough of a documentation bug to justify back-patching.

In passing, do some minor copy-editing in the same area, and add an entry
for LIKE under "Compatibility", since it's not exactly a faithful
implementation of the standard's feature.

Discussion: <20160728151154.AABE64016B@smtp.hushmail.com>
2016-07-28 13:26:58 -04:00
Tom Lane 19e972d558 Rethink node-level representation of partial-aggregation modes.
The original coding had three separate booleans representing partial
aggregation behavior, which was confusing, unreadable, and error-prone,
not least because the booleans weren't always listed in the same order.
It was also inadequate for the allegedly-desirable future extension to
support intermediate partial aggregation, because we'd need separate
markers for serialization and deserialization in such a case.

Merge these bools into an enum "AggSplit" to provide symbolic names for
the supported operating modes (and document what those are).  By assigning
the values of the enum constants carefully, we can treat AggSplit values
as options bitmasks so that tests of what to do aren't noticeably more
expensive than before.

While at it, get rid of Aggref.aggoutputtype.  That's not needed since
commit 59a3795c2 got rid of setrefs.c's special-purpose Aggref comparison
code, and it likewise seemed more confusing than helpful.

Assorted comment cleanup as well (there's still more that I want to do
in that line).

catversion bump for change in Aggref node contents.  Should be the last
one for partial-aggregation changes.

Discussion: <29309.1466699160@sss.pgh.pa.us>
2016-06-26 14:33:38 -04:00
Tom Lane f8ace5477e Fix type-safety problem with parallel aggregate serial/deserialization.
The original specification for this called for the deserialization function
to have signature "deserialize(serialtype) returns transtype", which is a
security violation if transtype is INTERNAL (which it always would be in
practice) and serialtype is not (which ditto).  The patch blithely overrode
the opr_sanity check for that, which was sloppy-enough work in itself,
but the indisputable reason this cannot be allowed to stand is that CREATE
FUNCTION will reject such a signature and thus it'd be impossible for
extensions to create parallelizable aggregates.

The minimum fix to make the signature type-safe is to add a second, dummy
argument of type INTERNAL.  But to lock it down a bit more and make misuse
of INTERNAL-accepting functions less likely, let's get rid of the ability
to specify a "serialtype" for an aggregate and just say that the only
useful serialtype is BYTEA --- which, in practice, is the only interesting
value anyway, due to the usefulness of the send/recv infrastructure for
this purpose.  That means we only have to allow "serialize(internal)
returns bytea" and "deserialize(bytea, internal) returns internal" as
the signatures for these support functions.

In passing fix bogus signature of int4_avg_combine, which I found thanks
to adding an opr_sanity check on combinefunc signatures.

catversion bump due to removing pg_aggregate.aggserialtype and adjusting
signatures of assorted built-in functions.

David Rowley and Tom Lane

Discussion: <27247.1466185504@sss.pgh.pa.us>
2016-06-22 16:52:41 -04:00
Bruce Momjian 3e9df858f0 Update comment about allowing GUCs to change scanning.
Reported-by: David G. Johnston

Discussion: CAKFQuwZZvnxwSq9tNtvL+uyuDKGgV91zR_agtPxQHRWMWQRP8g@mail.gmail.com
2016-06-21 20:23:31 -04:00
Tom Lane 915b703e16 Fix handling of argument and result datatypes for partial aggregation.
When doing partial aggregation, the args list of the upper (combining)
Aggref node is replaced by a Var representing the output of the partial
aggregation steps, which has either the aggregate's transition data type
or a serialized representation of that.  However, nodeAgg.c blindly
continued to use the args list as an indication of the user-level argument
types.  This broke resolution of polymorphic transition datatypes at
executor startup (though it accidentally failed to fail for the ANYARRAY
case, which is likely the only one anyone had tested).  Moreover, the
constructed FuncExpr passed to the finalfunc contained completely wrong
information, which would have led to bogus answers or crashes for any case
where the finalfunc examined that information (which is only likely to be
with polymorphic aggregates using a non-polymorphic transition type).

As an independent bug, apply_partialaggref_adjustment neglected to resolve
a polymorphic transition datatype before assigning it as the output type
of the lower-level Aggref node.  This again accidentally failed to fail
for ANYARRAY but would be unlikely to work in other cases.

To fix the first problem, record the user-level argument types in a
separate OID-list field of Aggref, and look to that rather than the args
list when asking what the argument types were.  (It turns out to be
convenient to include any "direct" arguments in this list too, although
those are not currently subject to being overwritten.)

Rather than adding yet another resolve_aggregate_transtype() call to fix
the second problem, add an aggtranstype field to Aggref, and store the
resolved transition type OID there when the planner first computes it.
(By doing this in the planner and not the parser, we can allow the
aggregate's transition type to change from time to time, although no DDL
support yet exists for that.)  This saves nothing of consequence for
simple non-polymorphic aggregates, but for polymorphic transition types
we save a catalog lookup during executor startup as well as several
planner lookups that are new in 9.6 due to parallel query planning.

In passing, fix an error that was introduced into count_agg_clauses_walker
some time ago: it was applying exprTypmod() to something that wasn't an
expression node at all, but a TargetEntry.  exprTypmod silently returned
-1 so that there was not an obvious failure, but this broke the intended
sensitivity of aggregate space consumption estimates to the typmod of
varchar and similar data types.  This part needs to be back-patched.

Catversion bump due to change of stored Aggref nodes.

Discussion: <8229.1466109074@sss.pgh.pa.us>
2016-06-17 21:44:37 -04:00
Robert Haas ede62e56fb Add VACUUM (DISABLE_PAGE_SKIPPING) for emergencies.
If you really want to vacuum every single page in the relation,
regardless of apparent visibility status or anything else, you can use
this option.  In previous releases, this behavior could be achieved
using VACUUM (FREEZE), but because we can now recognize all-frozen
pages as not needing to be frozen again, that no longer works.  There
should be no need for routine use of this option, but maybe bugs or
disaster recovery will necessitate its use.

Patch by me, reviewed by Andres Freund.
2016-06-17 15:48:57 -04:00
Robert Haas 4bc424b968 pgindent run for 9.6 2016-06-09 18:02:36 -04:00
Alvaro Herrera 4f04b66f97 Fix loose ends for SQL ACCESS METHOD objects
COMMENT ON ACCESS METHOD was missing; add it, along psql tab-completion
support for it.

psql was also missing a way to list existing access methods; the new \dA
command does that.

Also add tab-completion support for DROP ACCESS METHOD.

Author: Michael Paquier
Discussion: https://www.postgresql.org/message-id/CAB7nPqTzdZdu8J7EF8SXr_R2U5bSUUYNOT3oAWBZdEoggnwhGA@mail.gmail.com
2016-06-07 17:59:34 -04:00
Tom Lane 05104f6936 Fix grammar's AND/OR flattening to work with operator_precedence_warning.
It'd be good for "(x AND y) AND z" to produce a three-child AND node
whether or not operator_precedence_warning is on, but that failed to
happen when it's on because makeAndExpr() didn't look through the added
AEXPR_PAREN node.  This has no effect on generated plans because prepqual.c
would flatten the AND nest anyway; but it does affect the number of parens
printed in ruleutils.c, for example.  I'd already fixed some similar
hazards in parse_expr.c in commit abb164655, but didn't think to search
gram.y for problems of this ilk.  Per gripe from Jean-Pierre Pelletier.

Report: <fa0535ec6d6428cfec40c7e8a6d11156@mail.gmail.com>
2016-06-03 19:12:29 -04:00
Tom Lane b898eb6367 Remove option to write USING before opclass name in CREATE INDEX.
Dating back to commit f10b63923, our grammar has allowed "USING" to
optionally appear before an opclass name in CREATE INDEX (and, lately,
some related places such as ON CONFLICT specifications).  Nikolay Shaplov
noticed that this syntax existed but wasn't documented, and proposed
documenting it.  But what seems like a better idea is to remove the
production, thereby making the code match the docs not vice versa.
This isn't our usual modus operandi for such cases, but there are a
couple of good reasons to proceed this way:

* So far as I can find, this syntax has never been documented anywhere.
It isn't relied on by any of our own code or test cases, and there seems
little reason to suppose that it's been used in the wild either.

* Documenting it would mean that there would be two separate uses of
USING in the CREATE INDEX syntax, the other being "USING access_method".
That can lead to nothing but confusion.

So, let's just remove it.  On the off chance that somebody somewhere
is using it, this isn't something to back-patch, but we can fix it
in HEAD.

Discussion: <1593237.l7oKHRpxSe@nataraj-amd64>
2016-05-25 19:11:00 -04:00
Tom Lane 465e09da63 Add support for more extensive testing of raw_expression_tree_walker().
If RAW_EXPRESSION_COVERAGE_TEST is defined, do a no-op tree walk over
every basic DML statement submitted to parse analysis.  If we'd had this
in place earlier, bug #14153 would have been caught by buildfarm testing.
The difficulty is that raw_expression_tree_walker() is only used in
limited cases involving CTEs (particularly recursive ones), so it's
very easy for an oversight in it to not be noticed during testing of a
seemingly-unrelated feature.

The type of error we can expect to catch with this is complete omission
of a node type from raw_expression_tree_walker(), and perhaps also
recursion into a field that doesn't contain a node tree, though that
would be an unlikely mistake.  It won't catch failure to add new fields
that need to be recursed into, unfortunately.

I'll go enable this on one or two of my own buildfarm animals once
bug #14153 is dealt with.

Discussion: <27861.1464040417@sss.pgh.pa.us>
2016-05-23 19:08:26 -04:00
Tom Lane abb164655c Fix unexpected side-effects of operator_precedence_warning.
The implementation of that feature involves injecting nodes into the
raw parsetree where explicit parentheses appear.  Various places in
parse_expr.c that test to see "is this child node of type Foo" need to
look through such nodes, else we'll get different behavior when
operator_precedence_warning is on than when it is off.  Note that we only
need to handle this when testing untransformed child nodes, since the
AEXPR_PAREN nodes will be gone anyway after transformExprRecurse.

Per report from Scott Ribe and additional code-reading.  Back-patch
to 9.5 where this feature was added.

Report: <ED37E303-1B0A-4CD8-8E1E-B9C4C2DD9A17@elevated-dev.com>
2016-04-21 23:17:36 -04:00
Teodor Sigaev 8b99edefca Revert CREATE INDEX ... INCLUDING ...
It's not ready yet, revert two commits
690c543550 - unstable test output
386e3d7609 - patch itself
2016-04-08 21:52:13 +03:00
Teodor Sigaev 386e3d7609 CREATE INDEX ... INCLUDING (column[, ...])
Now indexes (but only B-tree for now) can contain "extra" column(s) which
doesn't participate in index structure, they are just stored in leaf
tuples. It allows to use index only scan by using single index instead
of two or more indexes.

Author: Anastasia Lubennikova with minor editorializing by me
Reviewers: David Rowley, Peter Geoghegan, Jeff Janes
2016-04-08 19:45:59 +03:00
Tom Lane de94e2af18 Run pgindent on a batch of (mostly-planner-related) source files.
Getting annoyed at the amount of unrelated chatter I get from pgindent'ing
Rowley's unique-joins patch.  Re-indent all the files it touches.
2016-04-06 11:34:02 -04:00
Alvaro Herrera f2fcad27d5 Support ALTER THING .. DEPENDS ON EXTENSION
This introduces a new dependency type which marks an object as depending
on an extension, such that if the extension is dropped, the object
automatically goes away; and also, if the database is dumped, the object
is included in the dump output.  Currently the grammar supports this for
indexes, triggers, materialized views and functions only, although the
utility code is generic so adding support for more object types is a
matter of touching the parser rules only.

Author: Abhijit Menon-Sen
Reviewed-by: Alexander Korotkov, Álvaro Herrera
Discussion: http://www.postgresql.org/message-id/20160115062649.GA5068@toroid.org
2016-04-05 18:38:54 -03:00
Alvaro Herrera f402b99501 Type names should not be quoted
Our actual convention, contrary to what I said in 59a2111b23, is not to
quote type names, as evidenced by unquoted use of format_type_be()
result value in error messages.  Remove quotes from recently tweaked
messages accordingly.

Per note from Tom Lane
2016-04-01 13:35:48 -03:00
Robert Haas 5fe5a2cee9 Allow aggregate transition states to be serialized and deserialized.
This is necessary infrastructure for supporting parallel aggregation
for aggregates whose transition type is "internal".  Such values
can't be passed between cooperating processes, because they are
just pointers.

David Rowley, reviewed by Tomas Vondra and by me.
2016-03-29 15:04:05 -04:00
Alvaro Herrera 59a2111b23 Improve internationalization of messages involving type names
Change the slightly different variations of the message
  function FOO must return type BAR
to a single wording, removing the variability in type name so that they
all create a single translation entry; since the type name is not to be
translated, there's no point in it being part of the message anyway.

Also, change them all to use the same quoting convention, namely that
the function name is not to be quoted but the type name is.  (I'm not
quite sure why this is so, but it's the clear majority.)

Some similar messages such as "encoding conversion function FOO must ..."
are also changed.
2016-03-28 14:24:37 -03:00
Tom Lane c1156411ad Move psql's psqlscan.l into src/fe_utils.
This completes (at least for now) the project of getting rid of ad-hoc
linkages among the src/bin/ subdirectories.  Everything they share is now
in src/fe_utils/ and is included from a static library at link time.

A side benefit is that we can restore the FLEX_NO_BACKUP check for
psqlscanslash.l.  We might need to think of another way to do that check
if we ever need to build two lexers with that property in the same source
directory, but there's no foreseeable reason to need that.
2016-03-24 20:28:47 -04:00