Commit Graph

85 Commits

Author SHA1 Message Date
Peter Eisentraut 0e1539ba0d Add some const decorations to prototypes
Reviewed-by: Fabien COELHO <coelho@cri.ensmp.fr>
2017-11-10 13:38:57 -05:00
Tom Lane 382ceffdf7 Phase 3 of pgindent updates.
Don't move parenthesized lines to the left, even if that means they
flow past the right margin.

By default, BSD indent lines up statement continuation lines that are
within parentheses so that they start just to the right of the preceding
left parenthesis.  However, traditionally, if that resulted in the
continuation line extending to the right of the desired right margin,
then indent would push it left just far enough to not overrun the margin,
if it could do so without making the continuation line start to the left of
the current statement indent.  That makes for a weird mix of indentations
unless one has been completely rigid about never violating the 80-column
limit.

This behavior has been pretty universally panned by Postgres developers.
Hence, disable it with indent's new -lpl switch, so that parenthesized
lines are always lined up with the preceding left paren.

This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.

Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 15:35:54 -04:00
Tom Lane c7b8998ebb Phase 2 of pgindent updates.
Change pg_bsd_indent to follow upstream rules for placement of comments
to the right of code, and remove pgindent hack that caused comments
following #endif to not obey the general rule.

Commit e3860ffa4d wasn't actually using
the published version of pg_bsd_indent, but a hacked-up version that
tried to minimize the amount of movement of comments to the right of
code.  The situation of interest is where such a comment has to be
moved to the right of its default placement at column 33 because there's
code there.  BSD indent has always moved right in units of tab stops
in such cases --- but in the previous incarnation, indent was working
in 8-space tab stops, while now it knows we use 4-space tabs.  So the
net result is that in about half the cases, such comments are placed
one tab stop left of before.  This is better all around: it leaves
more room on the line for comment text, and it means that in such
cases the comment uniformly starts at the next 4-space tab stop after
the code, rather than sometimes one and sometimes two tabs after.

Also, ensure that comments following #endif are indented the same
as comments following other preprocessor commands such as #else.
That inconsistency turns out to have been self-inflicted damage
from a poorly-thought-through post-indent "fixup" in pgindent.

This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.

Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 15:19:25 -04:00
Tom Lane e3860ffa4d Initial pgindent run with pg_bsd_indent version 2.0.
The new indent version includes numerous fixes thanks to Piotr Stefaniak.
The main changes visible in this commit are:

* Nicer formatting of function-pointer declarations.
* No longer unexpectedly removes spaces in expressions using casts,
  sizeof, or offsetof.
* No longer wants to add a space in "struct structname *varname", as
  well as some similar cases for const- or volatile-qualified pointers.
* Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely.
* Fixes bug where comments following declarations were sometimes placed
  with no space separating them from the code.
* Fixes some odd decisions for comments following case labels.
* Fixes some cases where comments following code were indented to less
  than the expected column 33.

On the less good side, it now tends to put more whitespace around typedef
names that are not listed in typedefs.list.  This might encourage us to
put more effort into typedef name collection; it's not really a bug in
indent itself.

There are more changes coming after this round, having to do with comment
indentation and alignment of lines appearing within parentheses.  I wanted
to limit the size of the diffs to something that could be reviewed without
one's eyes completely glazing over, so it seemed better to split up the
changes as much as practical.

Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 14:39:04 -04:00
Tom Lane e7941a9766 Replace over-optimistic Assert in partitioning code with a runtime test.
get_partition_parent felt that it could simply Assert that systable_getnext
found a tuple.  This is unlike any other caller of that function, and it's
unsafe IMO --- in fact, the reason I noticed it was that the Assert failed.
(OK, I was working with known-inconsistent catalog contents, but I wasn't
expecting the DB to fall over quite that violently.  The behavior in a
non-assert-enabled build wouldn't be very nice, either.)  Fix it to do what
other callers do, namely an actual runtime-test-and-elog.

Also, standardize the wording of elog messages that are complaining about
unexpected failure of systable_getnext.  90% of them say "could not find
tuple for <object>", so make the remainder do likewise.  Many of the
holdouts were using the phrasing "cache lookup failed", which is outright
misleading since no catcache search is involved.
2017-06-04 16:20:03 -04:00
Tom Lane 9209e07605 Ensure commands in extension scripts see the results of preceding DDL.
Due to a missing CommandCounterIncrement() call, parsing of a non-utility
command in an extension script would not see the effects of the immediately
preceding DDL command, unless that command's execution ends with
CommandCounterIncrement() internally ... which some do but many don't.
Report by Philippe Beaudoin, diagnosis by Julien Rouhaud.

Rather remarkably, this bug has evaded detection since extensions were
invented, so back-patch to all supported branches.

Discussion: https://postgr.es/m/2cf7941e-4e41-7714-3de8-37b1a8f74dff@free.fr
2017-05-02 18:06:09 -04:00
Tom Lane 8f0530f580 Improve castNode notation by introducing list-extraction-specific variants.
This extends the castNode() notation introduced by commit 5bcab1114 to
provide, in one step, extraction of a list cell's pointer and coercion to
a concrete node type.  For example, "lfirst_node(Foo, lc)" is the same
as "castNode(Foo, lfirst(lc))".  Almost half of the uses of castNode
that have appeared so far include a list extraction call, so this is
pretty widely useful, and it saves a few more keystrokes compared to the
old way.

As with the previous patch, back-patch the addition of these macros to
pg_list.h, so that the notation will be available when back-patching.

Patch by me, after an idea of Andrew Gierth's.

Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us
2017-04-10 13:51:53 -04:00
Kevin Grittner 18ce3a4ab2 Add infrastructure to support EphemeralNamedRelation references.
A QueryEnvironment concept is added, which allows new types of
objects to be passed into queries from parsing on through
execution.  At this point, the only thing implemented is a
collection of EphemeralNamedRelation objects -- relations which
can be referenced by name in queries, but do not exist in the
catalogs.  The only type of ENR implemented is NamedTuplestore, but
provision is made to add more types fairly easily.

An ENR can carry its own TupleDesc or reference a relation in the
catalogs by relid.

Although these features can be used without SPI, convenience
functions are added to SPI so that ENRs can easily be used by code
run through SPI.

The initial use of all this is going to be transition tables in
AFTER triggers, but that will be added to each PL as a separate
commit.

An incidental effect of this patch is to produce a more informative
error message if an attempt is made to modify the contents of a CTE
from a referencing DML statement.  No tests previously covered that
possibility, so one is added.

Kevin Grittner and Thomas Munro
Reviewed by Heikki Linnakangas, David Fetter, and Thomas Munro
with valuable comments and suggestions from many others
2017-03-31 23:17:18 -05:00
Robert Haas 691b8d5928 Allow for parallel execution whenever ExecutorRun() is done only once.
Previously, it was unsafe to execute a plan in parallel if
ExecutorRun() might be called with a non-zero row count.  However,
it's quite easy to fix things up so that we can support that case,
provided that it is known that we will never call ExecutorRun() a
second time for the same QueryDesc.  Add infrastructure to signal
this, and cross-checks to make sure that a caller who claims this is
true doesn't later reneg.

While that pattern never happens with queries received directly from a
client -- there's no way to know whether multiple Execute messages
will be sent unless the first one requests all the rows -- it's pretty
common for queries originating from procedural languages, which often
limit the result to a single tuple or to a user-specified number of
tuples.

This commit doesn't actually enable parallelism in any additional
cases, because currently none of the places that would be able to
benefit from this infrastructure pass CURSOR_OPT_PARALLEL_OK in the
first place, but it makes it much more palatable to pass
CURSOR_OPT_PARALLEL_OK in places where we currently don't, because it
eliminates some cases where we'd end up having to run the parallel
plan serially.

Patch by me, based on some ideas from Rafia Sabih and corrected by
Rafia Sabih based on feedback from Dilip Kumar and myself.

Discussion: http://postgr.es/m/CA+TgmobXEhvHbJtWDuPZM9bVSLiTj-kShxQJ2uM5GPDze9fRYA@mail.gmail.com
2017-03-23 13:14:36 -04:00
Noah Misch 3a0d473192 Use wrappers of PG_DETOAST_DATUM_PACKED() more.
This makes almost all core code follow the policy introduced in the
previous commit.  Specific decisions:

- Text search support functions with char* and length arguments, such as
  prsstart and lexize, may receive unaligned strings.  I doubt
  maintainers of non-core text search code will notice.

- Use plain VARDATA() on values detoasted or synthesized earlier in the
  same function.  Use VARDATA_ANY() on varlenas sourced outside the
  function, even if they happen to always have four-byte headers.  As an
  exception, retain the universal practice of using VARDATA() on return
  values of SendFunctionCall().

- Retain PG_GETARG_BYTEA_P() in pageinspect.  (Page images are too large
  for a one-byte header, so this misses no optimization.)  Sites that do
  not call get_page_from_raw() typically need the four-byte alignment.

- For now, do not change btree_gist.  Its use of four-byte headers in
  memory is partly entangled with storage of 4-byte headers inside
  GBT_VARKEY, on disk.

- For now, do not change gtrgm_consistent() or gtrgm_distance().  They
  incorporate the varlena header into a cache, and there are multiple
  credible implementation strategies to consider.
2017-03-12 19:35:34 -04:00
Peter Eisentraut 8b6d6cf853 Remove objname/objargs split for referring to objects
In simpler times, it might have worked to refer to all kinds of objects
by a list of name components and an optional argument list.  But this
doesn't work for all objects, which has resulted in a collection of
hacks to place various other nodes types into these fields, which have
to be unpacked at the other end.  This makes it also weird to represent
lists of such things in the grammar, because they would have to be lists
of singleton lists, to make the unpacking work consistently.  The other
problem is that keeping separate name and args fields makes it awkward
to deal with lists of functions.

Change that by dropping the objargs field and have objname, renamed to
object, be a generic Node, which can then be flexibly assigned and
managed using the normal Node mechanisms.  In many cases it will still
be a List of names, in some cases it will be a string Value, for types
it will be the existing Typename, for functions it will now use the
existing ObjectWithArgs node type.  Some of the more obscure object
types still use somewhat arbitrary nested lists.

Reviewed-by: Jim Nasby <Jim.Nasby@BlueTreble.com>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2017-03-06 13:31:47 -05:00
Tom Lane ab02896510 Provide CatalogTupleDelete() as a wrapper around simple_heap_delete().
This extends the work done in commit 2f5c9d9c9 to provide a more nearly
complete abstraction layer hiding the details of index updating for catalog
changes.  That commit only invented abstractions for catalog inserts and
updates, leaving nearby code for catalog deletes still calling the
heap-level routines directly.  That seems rather ugly from here, and it
does little to help if we ever want to shift to a storage system in which
indexing work is needed at delete time.

Hence, create a wrapper function CatalogTupleDelete(), and replace calls
of simple_heap_delete() on catalog tuples with it.  There are now very
few direct calls of [simple_]heap_delete remaining in the tree.

Discussion: https://postgr.es/m/462.1485902736@sss.pgh.pa.us
2017-02-01 16:13:30 -05:00
Alvaro Herrera 2f5c9d9c9c Tweak catalog indexing abstraction for upcoming WARM
Split the existing CatalogUpdateIndexes into two different routines,
CatalogTupleInsert and CatalogTupleUpdate, which do both the heap
insert/update plus the index update.  This removes over 300 lines of
boilerplate code all over src/backend/catalog/ and src/backend/commands.
The resulting code is much more pleasing to the eye.

Also, by encapsulating what happens in detail during an UPDATE, this
facilitates the upcoming WARM patch, which is going to add a few more
lines to the update case making the boilerplate even more boring.

The original CatalogUpdateIndexes is removed; there was only one use
left, and since it's just three lines, we can as well expand it in place
there.  We could keep it, but WARM is going to break all the UPDATE
out-of-core callsites anyway, so there seems to be no benefit in doing
so.

Author: Pavan Deolasee
Discussion: https://www.postgr.es/m/CABOikdOcFYSZ4vA2gYfs=M2cdXzXX4qGHeEiW3fu9PCfkHLa2A@mail.gmail.com
2017-01-31 18:42:24 -03:00
Stephen Frost e54f75722c Handle ALTER EXTENSION ADD/DROP with pg_init_privs
In commit 6c268df, pg_init_privs was added to track the initial
privileges of catalog objects and extensions.  Unfortunately, that
commit didn't include understanding of ALTER EXTENSION ADD/DROP, which
allows the objects associated with an extension to be changed after the
initial CREATE EXTENSION script has been run.

The result of this meant that ACLs for objects added through
ALTER EXTENSION ADD were not recorded into pg_init_privs and we would
end up including those ACLs in pg_dump when we shouldn't have.

This commit corrects that by making sure to have pg_init_privs updated
when ALTER EXTENSION ADD/DROP is run, recording the permissions as they
are at ALTER EXTENSION ADD time, and removing any if/when ALTER
EXTENSION DROP is called.

This issue was pointed out by Moshe Jacobson as commentary on bug #14456
(which was actually a bug about versions prior to 9.6 not handling
custom ACLs on extensions correctly, an issue now addressed with
pg_init_privs in 9.6).

Back-patch to 9.6 where pg_init_privs was introduced.
2017-01-29 23:05:07 -05:00
Tom Lane 7afd56c3c6 Use castNode() in a bunch of statement-list-related code.
When I wrote commit ab1f0c822, I really missed the castNode() macro that
Peter E. had proposed shortly before.  This back-fills the uses I would
have put it to.  It's probably not all that significant, but there are
more assertions here than there were before, and conceivably they will
help catch any bugs associated with those representation changes.

I left behind a number of usages like "(Query *) copyObject(query_var)".
Those could have been converted as well, but Peter has proposed another
notational improvement that would handle copyObject cases automatically,
so I let that be for now.
2017-01-26 22:09:34 -05:00
Peter Eisentraut f21a563d25 Move some things from builtins.h to new header files
This avoids that builtins.h has to include additional header files.
2017-01-20 20:29:53 -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
Bruce Momjian 1d25779284 Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
Tom Lane 40b449ae84 Allow CREATE EXTENSION to follow extension update paths.
Previously, to update an extension you had to produce both a version-update
script and a new base installation script.  It's become more and more
obvious that that's tedious, duplicative, and error-prone.  This patch
attempts to improve matters by allowing the new base installation script
to be omitted.  CREATE EXTENSION will install a requested version if it
can find a base script and a chain of update scripts that will get there.
As in the existing update logic, shorter chains are preferred if there's
more than one possibility, with an arbitrary tie-break rule for chains
of equal length.

Also adjust the pg_available_extension_versions view to show such versions
as installable.

While at it, refactor the code so that CASCADE processing works for
extensions requested during ApplyExtensionUpdates().  Without this,
addition of a new requirement in an updated extension would require
creating a new base script, even if there was no other reason to do that.
(It would be easy at this point to add a CASCADE option to ALTER EXTENSION
UPDATE, to allow the same thing to happen during a manually-commanded
version update, but I have not done that here.)

Tom Lane, reviewed by Andres Freund

Discussion: <20160905005919.jz2m2yh3und2dsuy@alap3.anarazel.de>
2016-09-11 14:15:07 -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 25794e841e Cosmetic code cleanup in commands/extension.c.
Some of the comments added by the CREATE EXTENSION CASCADE patch were
a bit sloppy, and I didn't care for redeclaring the same local variable
inside a nested block either.  No functional changes.
2016-09-05 18:53:33 -04:00
Peter Eisentraut 40fcfec82c Message style improvements 2016-07-25 22:07:44 -04:00
Robert Haas 4bc424b968 pgindent run for 9.6 2016-06-09 18:02:36 -04:00
Bruce Momjian ee94300446 Update copyright for 2016
Backpatch certain files through 9.1
2016-01-02 13:33:40 -05:00
Peter Eisentraut 5db837d3f2 Message improvements 2015-11-16 21:39:23 -05:00
Andres Freund b67aaf21e8 Add CASCADE support for CREATE EXTENSION.
Without CASCADE, if an extension has an unfullfilled dependency on
another extension, CREATE EXTENSION ERRORs out with "required extension
... is not installed". That is annoying, especially when that dependency
is an implementation detail of the extension, rather than something the
extension's user can make sense of.

In addition to CASCADE this also includes a small set of regression
tests around CREATE EXTENSION.

Author: Petr Jelinek, editorialized by Michael Paquier, Andres Freund
Reviewed-By: Michael Paquier, Andres Freund, Jeff Janes
Discussion: 557E0520.3040800@2ndquadrant.com
2015-10-03 18:23:40 +02:00
Robert Haas 7aea8e4f2d Determine whether it's safe to attempt a parallel plan for a query.
Commit 924bcf4f16 introduced a framework
for parallel computation in PostgreSQL that makes most but not all
built-in functions safe to execute in parallel mode.  In order to have
parallel query, we'll need to be able to determine whether that query
contains functions (either built-in or user-defined) that cannot be
safely executed in parallel mode.  This requires those functions to be
labeled, so this patch introduces an infrastructure for that.  Some
functions currently labeled as safe may need to be revised depending on
how pending issues related to heavyweight locking under paralllelism
are resolved.

Parallel plans can't be used except for the case where the query will
run to completion.  If portal execution were suspended, the parallel
mode restrictions would need to remain in effect during that time, but
that might make other queries fail.  Therefore, this patch introduces
a framework that enables consideration of parallel plans only when it
is known that the plan will be run to completion.  This probably needs
some refinement; for example, at bind time, we do not know whether a
query run via the extended protocol will be execution to completion or
run with a limited fetch count.  Having the client indicate its
intentions at bind time would constitute a wire protocol break.  Some
contexts in which parallel mode would be safe are not adjusted by this
patch; the default is not to try parallel plans except from call sites
that have been updated to say that such plans are OK.

This commit doesn't introduce any parallel paths or plans; it just
provides a way to determine whether they could potentially be used.
I'm committing it on the theory that the remaining parallel sequential
scan patches will also get committed to this release, hopefully in the
not-too-distant future.

Robert Haas and Amit Kapila.  Reviewed (in earlier versions) by Noah
Misch.
2015-09-16 15:38:47 -04:00
Heikki Linnakangas cb2acb1081 Add missing_ok option to the SQL functions for reading files.
This makes it possible to use the functions without getting errors, if there
is a chance that the file might be removed or renamed concurrently.
pg_rewind needs to do just that, although this could be useful for other
purposes too. (The changes to pg_rewind to use these functions will come in
a separate commit.)

The read_binary_file() function isn't very well-suited for extensions.c's
purposes anymore, if it ever was. So bite the bullet and make a copy of it
in extension.c, tailored for that use case. This seems better than the
accidental code reuse, even if it's a some more lines of code.

Michael Paquier, with plenty of kibitzing by me.
2015-06-28 21:35:46 +03:00
Alvaro Herrera 31eae6028e Allow CURRENT/SESSION_USER to be used in certain commands
Commands such as ALTER USER, ALTER GROUP, ALTER ROLE, GRANT, and the
various ALTER OBJECT / OWNER TO, as well as ad-hoc clauses related to
roles such as the AUTHORIZATION clause of CREATE SCHEMA, the FOR clause
of CREATE USER MAPPING, and the FOR ROLE clause of ALTER DEFAULT
PRIVILEGES can now take the keywords CURRENT_USER and SESSION_USER as
user specifiers in place of an explicit user name.

This commit also fixes some quite ugly handling of special standards-
mandated syntax in CREATE USER MAPPING, which in particular would fail
to work in presence of a role named "current_user".

The special role specifiers PUBLIC and NONE also have more consistent
handling now.

Also take the opportunity to add location tracking to user specifiers.

Authors: Kyotaro Horiguchi.  Heavily reworked by Álvaro Herrera.
Reviewed by: Rushabh Lathia, Adam Brightwell, Marti Raudsepp.
2015-03-09 15:41:54 -03:00
Alvaro Herrera a2e35b53c3 Change many routines to return ObjectAddress rather than OID
The changed routines are mostly those that can be directly called by
ProcessUtilitySlow; the intention is to make the affected object
information more precise, in support for future event trigger changes.
Originally it was envisioned that the OID of the affected object would
be enough, and in most cases that is correct, but upon actually
implementing the event trigger changes it turned out that ObjectAddress
is more widely useful.

Additionally, some command execution routines grew an output argument
that's an object address which provides further info about the executed
command.  To wit:

* for ALTER DOMAIN / ADD CONSTRAINT, it corresponds to the address of
  the new constraint

* for ALTER OBJECT / SET SCHEMA, it corresponds to the address of the
  schema that originally contained the object.

* for ALTER EXTENSION {ADD, DROP} OBJECT, it corresponds to the address
  of the object added to or dropped from the extension.

There's no user-visible change in this commit, and no functional change
either.

Discussion: 20150218213255.GC6717@tamriel.snowman.net
Reviewed-By: Stephen Frost, Andres Freund
2015-03-03 14:10:50 -03:00
Bruce Momjian 4baaf863ec Update copyright for 2015
Backpatch certain files through 9.0
2015-01-06 11:43:47 -05:00
Robert Haas f5d9698a84 Add infrastructure to save and restore GUC values.
This is further infrastructure for parallelism.

Amit Khandekar, Noah Misch, Robert Haas
2014-11-24 16:37:56 -05:00
Bruce Momjian 0a78320057 pgindent run for 9.4
This includes removing tabs after periods in C comments, which was
applied to back branches, so this change should not effect backpatching.
2014-05-06 12:12:18 -04:00
Tom Lane 769065c1b2 Prefer pg_any_to_server/pg_server_to_any over pg_do_encoding_conversion.
A large majority of the callers of pg_do_encoding_conversion were
specifying the database encoding as either source or target of the
conversion, meaning that we can use the less general functions
pg_any_to_server/pg_server_to_any instead.

The main advantage of using the latter functions is that they can make use
of a cached conversion-function lookup in the common case that the other
encoding is the current client_encoding.  It's notationally cleaner too in
most cases, not least because of the historical artifact that the latter
functions use "char *" rather than "unsigned char *" in their APIs.

Note that pg_any_to_server will apply an encoding verification step in
some cases where pg_do_encoding_conversion would have just done nothing.
This seems to me to be a good idea at most of these call sites, though
it partially negates the performance benefit.

Per discussion of bug #9210.
2014-02-23 16:59:05 -05:00
Bruce Momjian 7e04792a1c Update copyright for 2014
Update all files in head, and files COPYRIGHT and legal.sgml in all back
branches.
2014-01-07 16:05:30 -05:00
Robert Haas 568d4138c6 Use an MVCC snapshot, rather than SnapshotNow, for catalog scans.
SnapshotNow scans have the undesirable property that, in the face of
concurrent updates, the scan can fail to see either the old or the new
versions of the row.  In many cases, we work around this by requiring
DDL operations to hold AccessExclusiveLock on the object being
modified; in some cases, the existing locking is inadequate and random
failures occur as a result.  This commit doesn't change anything
related to locking, but will hopefully pave the way to allowing lock
strength reductions in the future.

The major issue has held us back from making this change in the past
is that taking an MVCC snapshot is significantly more expensive than
using a static special snapshot such as SnapshotNow.  However, testing
of various worst-case scenarios reveals that this problem is not
severe except under fairly extreme workloads.  To mitigate those
problems, we avoid retaking the MVCC snapshot for each new scan;
instead, we take a new snapshot only when invalidation messages have
been processed.  The catcache machinery already requires that
invalidation messages be sent before releasing the related heavyweight
lock; else other backends might rely on locally-cached data rather
than scanning the catalog at all.  Thus, making snapshot reuse
dependent on the same guarantees shouldn't break anything that wasn't
already subtly broken.

Patch by me.  Review by Michael Paquier and Andres Freund.
2013-07-02 09:47:01 -04:00
Tom Lane 530acda4da Provide better message when CREATE EXTENSION can't find a target schema.
The new message (and SQLSTATE) matches the corresponding error cases in
namespace.c.

This was thought to be a "can't happen" case when extension.c was written,
so we didn't think hard about how to report it.  But it definitely can
happen in 9.2 and later, since we no longer require search_path to contain
any valid schema names.  It's probably also possible in 9.1 if search_path
came from a noninteractive source.  So, back-patch to all releases
containing this code.

Per report from Sean Chittenden, though this isn't exactly his patch.
2013-06-04 17:22:29 -04:00
Tom Lane f8db76e875 Editorialize a bit on new ProcessUtility() API.
Choose a saner ordering of parameters (adding a new input param after
the output params seemed a bit random), update the function's header
comment to match reality (cmon folks, is this really that hard?),
get rid of useless and sloppily-defined distinction between
PROCESS_UTILITY_SUBCOMMAND and PROCESS_UTILITY_GENERATED.
2013-04-28 00:18:45 -04:00
Robert Haas 05f3f9c7b2 Extend object-access hook machinery to support post-alter events.
This also slightly widens the scope of what we support in terms of
post-create events.

KaiGai Kohei, with a few changes, mostly to the comments, by me
2013-03-17 22:57:26 -04:00
Robert Haas f90cc26982 Code beautification for object-access hook machinery.
KaiGai Kohei
2013-03-06 20:53:25 -05:00
Bruce Momjian bd61a623ac Update copyrights for 2013
Fully update git head, and update back branches in ./COPYRIGHT and
legal.sgml files.
2013-01-01 17:15:01 -05:00
Robert Haas 82b1b213ca Adjust more backend functions to return OID rather than void.
This is again intended to support extensions to the event trigger
functionality.  This may go a bit further than we need for that
purpose, but there's some value in being consistent, and the OID
may be useful for other purposes also.

Dimitri Fontaine
2012-12-29 07:55:37 -05:00
Robert Haas c504513f83 Adjust many backend functions to return OID rather than void.
Extracted from a larger patch by Dimitri Fontaine.  It is hoped that
this will provide infrastructure for enriching the new event trigger
functionality, but it seems possibly useful for other purposes as
well.
2012-12-23 18:37:58 -05:00
Tom Lane 343c2a865b Fix pg_extension_config_dump() to handle update cases more sanely.
If pg_extension_config_dump() is executed again for a table already listed
in the extension's extconfig, the code was blindly making a new array entry.
This does not seem useful.  Fix it to replace the existing array entry
instead, so that it's possible for extension update scripts to alter the
filter conditions for configuration tables.

In addition, teach ALTER EXTENSION DROP TABLE to check for an extconfig
entry for the target table, and remove it if present.  This is not a 100%
solution because it's allowed for an extension update script to just
summarily DROP a member table, and that code path doesn't go through
ExecAlterExtensionContentsStmt.  We could probably make that case clean
things up if we had to, but it would involve sticking a very ugly wart
somewhere in the guts of dependency.c.  Since on the whole it seems quite
unlikely that extension updates would want to remove pre-existing
configuration tables, making the case possible with an explicit command
seems sufficient.

Per bug #7756 from Regina Obe.  Back-patch to 9.1 where extensions were
introduced.
2012-12-20 16:31:42 -05:00
Alvaro Herrera 04f28bdb84 Fix ALTER EXTENSION / SET SCHEMA
In its original conception, it was leaving some objects into the old
schema, but without their proper pg_depend entries; this meant that the
old schema could be dropped, causing future pg_dump calls to fail on the
affected database.  This was originally reported by Jeff Frost as #6704;
there have been other complaints elsewhere that can probably be traced
to this bug.

To fix, be more consistent about altering a table's subsidiary objects
along the table itself; this requires some restructuring in how tables
are relocated when altering an extension -- hence the new
AlterTableNamespaceInternal routine which encapsulates it for both the
ALTER TABLE and the ALTER EXTENSION cases.

There was another bug lurking here, which was unmasked after fixing the
previous one: certain objects would be reached twice via the dependency
graph, and the second attempt to move them would cause the entire
operation to fail.  Per discussion, it seems the best fix for this is to
do more careful tracking of objects already moved: we now maintain a
list of moved objects, to avoid attempting to do it twice for the same
object.

Authors: Alvaro Herrera, Dimitri Fontaine
Reviewed by Tom Lane
2012-10-31 10:52:55 -03:00
Tom Lane fb34e94d21 Support CREATE SCHEMA IF NOT EXISTS.
Per discussion, schema-element subcommands are not allowed together with
this option, since it's not very obvious what should happen to the element
objects.

Fabrízio de Royes Mello
2012-10-03 19:47:11 -04:00
Alvaro Herrera 994c36e01d refactor ALTER some-obj SET OWNER implementation
Remove duplicate implementation of catalog munging and miscellaneous
privilege and consistency checks.  Instead rely on already existing data
in objectaddress.c to do the work.

Author: KaiGai Kohei
Tweaked by me
Reviewed by Robert Haas
2012-10-03 18:07:46 -03:00
Alvaro Herrera c219d9b0a5 Split tuple struct defs from htup.h to htup_details.h
This reduces unnecessary exposure of other headers through htup.h, which
is very widely included by many files.

I have chosen to move the function prototypes to the new file as well,
because that means htup.h no longer needs to include tupdesc.h.  In
itself this doesn't have much effect in indirect inclusion of tupdesc.h
throughout the tree, because it's also required by execnodes.h; but it's
something to explore in the future, and it seemed best to do the htup.h
change now while I'm busy with it.
2012-08-30 16:52:35 -04:00
Alvaro Herrera 45326c5a11 Split resowner.h
This lets files that are mere users of ResourceOwner not automatically
include the headers for stuff that is managed by the resowner mechanism.
2012-08-28 18:02:07 -04:00
Tom Lane 4d642b5941 Disallow extensions from owning the schema they are assigned to.
This situation creates a dependency loop that confuses pg_dump and probably
other things.  Moreover, since the mental model is that the extension
"contains" schemas it owns, but "is contained in" its extschema (even
though neither is strictly true), having both true at once is confusing for
people too.  So prevent the situation from being set up.

Reported and patched by Thom Brown.  Back-patch to 9.1 where extensions
were added.
2012-08-15 11:28:03 -04:00