Commit Graph

585 Commits

Author SHA1 Message Date
Andres Freund 4f85fde8eb Introduce and use infrastructure for interrupt processing during client reads.
Up to now large swathes of backend code ran inside signal handlers
while reading commands from the client, to allow for speedy reaction to
asynchronous events. Most prominently shared invalidation and NOTIFY
handling. That means that complex code like the starting/stopping of
transactions is run in signal handlers...  The required code was
fragile and verbose, and is likely to contain bugs.

That approach also severely limited what could be done while
communicating with the client. As the read might be from within
openssl it wasn't safely possible to trigger an error, e.g. to cancel
a backend in idle-in-transaction state. We did that in some cases,
namely fatal errors, nonetheless.

Now that FE/BE communication in the backend employs non-blocking
sockets and latches to block, we can quite simply interrupt reads from
signal handlers by setting the latch. That allows us to signal an
interrupted read, which is supposed to be retried after returning from
within the ssl library.

As signal handlers now only need to set the latch to guarantee timely
interrupt processing, remove a fair amount of complicated & fragile
code from async.c and sinval.c.

We could now actually start to process some kinds of interrupts, like
sinval ones, more often that before, but that seems better done
separately.

This work will hopefully allow to handle cases like being blocked by
sending data, interrupting idle transactions and similar to be
implemented without too much effort.  In addition to allowing getting
rid of ImmediateInterruptOK, that is.

Author: Andres Freund
Reviewed-By: Heikki Linnakangas
2015-02-03 22:25:20 +01:00
Tom Lane 8e166e164c Rearrange explain.c's API so callers need not embed sizeof(ExplainState).
The folly of the previous arrangement was just demonstrated: there's no
convenient way to add fields to ExplainState without breaking ABI, even
if callers have no need to touch those fields.  Since we might well need
to do that again someday in back branches, let's change things so that
only explain.c has to have sizeof(ExplainState) compiled into it.  This
costs one extra palloc() per EXPLAIN operation, which is surely pretty
negligible.
2015-01-15 13:39:33 -05:00
Tom Lane a5cd70dcbc Improve performance of EXPLAIN with large range tables.
As of 9.3, ruleutils.c goes to some lengths to ensure that table and column
aliases used in its output are unique.  Of course this takes more time than
was required before, which in itself isn't fatal.  However, EXPLAIN was set
up so that recalculation of the unique aliases was repeated for each
subexpression printed in a plan.  That results in O(N^2) time and memory
consumption for large plan trees, which did not happen in older branches.

Fortunately, the expensive work is the same across a whole plan tree,
so there is no need to repeat it; we can do most of the initialization
just once per query and re-use it for each subexpression.  This buys
back most (not all) of the performance loss since 9.2.

We need an extra ExplainState field to hold the precalculated deparse
context.  That's no problem in HEAD, but in the back branches, expanding
sizeof(ExplainState) seems risky because third-party extensions might
have local variables of that struct type.  So, in 9.4 and 9.3, introduce
an auxiliary struct to keep sizeof(ExplainState) the same.  We should
refactor the APIs to avoid such local variables in future, but that's
material for a separate HEAD-only commit.

Per gripe from Alexey Bashtanov.  Back-patch to 9.3 where the issue
was introduced.
2015-01-15 13:18:12 -05:00
Bruce Momjian 4baaf863ec Update copyright for 2015
Backpatch certain files through 9.0
2015-01-06 11:43:47 -05:00
Alvaro Herrera 0ee98d1cbf pg_event_trigger_dropped_objects: add behavior flags
Add "normal" and "original" flags as output columns to the
pg_event_trigger_dropped_objects() function.  With this it's possible to
distinguish which objects, among those listed, need to be explicitely
referenced when trying to replicate a deletion.

This is necessary so that the list of objects can be pruned to the
minimum necessary to replicate the DROP command in a remote server that
might have slightly different schema (for instance, TOAST tables and
constraints with different names and such.)

Catalog version bumped due to change of function definition.

Reviewed by: Abhijit Menon-Sen, Stephen Frost, Heikki Linnakangas,
Robert Haas.
2014-12-19 15:00:45 -03:00
Simon Riggs fe263d115a REINDEX SCHEMA
Add new SCHEMA option to REINDEX and reindexdb.

Sawada Masahiko

Reviewed by Michael Paquier and Fabrízio de Royes Mello
2014-12-09 00:28:00 +09:00
Simon Riggs 618c9430a8 Event Trigger for table_rewrite
Generate a table_rewrite event when ALTER TABLE
attempts to rewrite a table. Provide helper
functions to identify table and reason.

Intended use case is to help assess or to react
to schema changes that might hold exclusive locks
for long periods.

Dimitri Fontaine, triggering an edit by Simon Riggs

Reviewed in detail by Michael Paquier
2014-12-08 00:55:28 +09:00
Heikki Linnakangas 2c03216d83 Revamp the WAL record format.
Each WAL record now carries information about the modified relation and
block(s) in a standardized format. That makes it easier to write tools that
need that information, like pg_rewind, prefetching the blocks to speed up
recovery, etc.

There's a whole new API for building WAL records, replacing the XLogRecData
chains used previously. The new API consists of XLogRegister* functions,
which are called for each buffer and chunk of data that is added to the
record. The new API also gives more control over when a full-page image is
written, by passing flags to the XLogRegisterBuffer function.

This also simplifies the XLogReadBufferForRedo() calls. The function can dig
the relation and block number from the WAL record, so they no longer need to
be passed as arguments.

For the convenience of redo routines, XLogReader now disects each WAL record
after reading it, copying the main data part and the per-block data into
MAXALIGNed buffers. The data chunks are not aligned within the WAL record,
but the redo routines can assume that the pointers returned by XLogRecGet*
functions are. Redo routines are now passed the XLogReaderState, which
contains the record in the already-disected format, instead of the plain
XLogRecord.

The new record format also makes the fixed size XLogRecord header smaller,
by removing the xl_len field. The length of the "main data" portion is now
stored at the end of the WAL record, and there's a separate header after
XLogRecord for it. The alignment padding at the end of XLogRecord is also
removed. This compansates for the fact that the new format would otherwise
be more bulky than the old format.

Reviewed by Andres Freund, Amit Kapila, Michael Paquier, Alvaro Herrera,
Fujii Masao.
2014-11-20 18:46:41 +02:00
Alvaro Herrera 85b506bbfc Get rid of SET LOGGED indexes persistence kludge
This removes ATChangeIndexesPersistence() introduced by f41872d0c1
which was too ugly to live for long.  Instead, the correct persistence
marking is passed all the way down to reindex_index, so that the
transient relation built to contain the index relfilenode can
get marked correctly right from the start.

Author: Fabrízio de Royes Mello
Review and editorialization by Michael Paquier
                                     and Álvaro Herrera
2014-11-15 01:19:49 -03:00
Heikki Linnakangas 2076db2aea Move the backup-block logic from XLogInsert to a new file, xloginsert.c.
xlog.c is huge, this makes it a little bit smaller, which is nice. Functions
related to putting together the WAL record are in xloginsert.c, and the
lower level stuff for managing WAL buffers and such are in xlog.c.

Also move the definition of XLogRecord to a separate header file. This
causes churn in the #includes of all the files that write WAL records, and
redo routines, but it avoids pulling in xlog.h into most places.

Reviewed by Michael Paquier, Alvaro Herrera, Andres Freund and Amit Kapila.
2014-11-06 13:55:36 +02:00
Tom Lane fd0f651a86 Test IsInTransactionChain, not IsTransactionBlock, in vac_update_relstats.
As noted by Noah Misch, my initial cut at fixing bug #11638 didn't cover
all cases where ANALYZE might be invoked in an unsafe context.  We need to
test the result of IsInTransactionChain not IsTransactionBlock; which is
notationally a pain because IsInTransactionChain requires an isTopLevel
flag, which would have to be passed down through several levels of callers.
I chose to pass in_outer_xact (ie, the result of IsInTransactionChain)
rather than isTopLevel per se, as that seemed marginally more apropos
for the intermediate functions to know about.
2014-10-30 13:04:06 -04:00
Tom Lane 90063a7612 Print planning time only in EXPLAIN ANALYZE, not plain EXPLAIN.
We've gotten enough push-back on that change to make it clear that it
wasn't an especially good idea to do it like that.  Revert plain EXPLAIN
to its previous behavior, but keep the extra output in EXPLAIN ANALYZE.
Per discussion.

Internally, I set this up as a separate flag ExplainState.summary that
controls printing of planning time and execution time.  For now it's
just copied from the ANALYZE option, but we could consider exposing it
to users.
2014-10-15 18:50:13 -04:00
Stephen Frost 6550b901fe Code review for row security.
Buildfarm member tick identified an issue where the policies in the
relcache for a relation were were being replaced underneath a running
query, leading to segfaults while processing the policies to be added
to a query.  Similar to how TupleDesc RuleLocks are handled, add in a
equalRSDesc() function to check if the policies have actually changed
and, if not, swap back the rsdesc field (using the original instead of
the temporairly built one; the whole structure is swapped and then
specific fields swapped back).  This now passes a CLOBBER_CACHE_ALWAYS
for me and should resolve the buildfarm error.

In addition to addressing this, add a new chapter in Data Definition
under Privileges which explains row security and provides examples of
its usage, change \d to always list policies (even if row security is
disabled- but note that it is disabled, or enabled with no policies),
rework check_role_for_policy (it really didn't need the entire policy,
but it did need to be using has_privs_of_role()), and change the field
in pg_class to relrowsecurity from relhasrowsecurity, based on
Heikki's suggestion.  Also from Heikki, only issue SET ROW_SECURITY in
pg_restore when talking to a 9.5+ server, list Bypass RLS in \du, and
document --enable-row-security options for pg_dump and pg_restore.

Lastly, fix a number of minor whitespace and typo issues from Heikki,
Dimitri, add a missing #include, per Peter E, fix a few minor
variable-assigned-but-not-used and resource leak issues from Coverity
and add tab completion for role attribute bypassrls as well.
2014-09-24 16:32:22 -04:00
Stephen Frost 491c029dbc Row-Level Security Policies (RLS)
Building on the updatable security-barrier views work, add the
ability to define policies on tables to limit the set of rows
which are returned from a query and which are allowed to be added
to a table.  Expressions defined by the policy for filtering are
added to the security barrier quals of the query, while expressions
defined to check records being added to a table are added to the
with-check options of the query.

New top-level commands are CREATE/ALTER/DROP POLICY and are
controlled by the table owner.  Row Security is able to be enabled
and disabled by the owner on a per-table basis using
ALTER TABLE .. ENABLE/DISABLE ROW SECURITY.

Per discussion, ROW SECURITY is disabled on tables by default and
must be enabled for policies on the table to be used.  If no
policies exist on a table with ROW SECURITY enabled, a default-deny
policy is used and no records will be visible.

By default, row security is applied at all times except for the
table owner and the superuser.  A new GUC, row_security, is added
which can be set to ON, OFF, or FORCE.  When set to FORCE, row
security will be applied even for the table owner and superusers.
When set to OFF, row security will be disabled when allowed and an
error will be thrown if the user does not have rights to bypass row
security.

Per discussion, pg_dump sets row_security = OFF by default to ensure
that exports and backups will have all data in the table or will
error if there are insufficient privileges to bypass row security.
A new option has been added to pg_dump, --enable-row-security, to
ask pg_dump to export with row security enabled.

A new role capability, BYPASSRLS, which can only be set by the
superuser, is added to allow other users to be able to bypass row
security using row_security = OFF.

Many thanks to the various individuals who have helped with the
design, particularly Robert Haas for his feedback.

Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean
Rasheed, with additional changes and rework by me.

Reviewers have included all of the above, Greg Smith,
Jeff McCormick, and Robert Haas.
2014-09-19 11:18:35 -04:00
Andres Freund 728f152e07 Add rmgr callback to name xlog record types for display purposes.
This is primarily useful for the upcoming pg_xlogdump --stats feature,
but also allows to remove some duplicated code in the rmgr_desc
routines.

Due to the separation and harmonization, the output of dipsplayed
records changes somewhat. But since this isn't enduser oriented
content that's ok.

It's potentially desirable to further change pg_xlogdump's display of
records. It previously wasn't possible to show the record type
separately from the description forcing it to be in the last
column. But that's better done in a separate commit.

Author: Abhijit Menon-Sen, slightly editorialized by me
Reviewed-By: Álvaro Herrera, Andres Freund, and Heikki Linnakangas
Discussion: 20140604104716.GA3989@toroid.org
2014-09-19 16:20:29 +02:00
Alvaro Herrera 301fcf33eb Have CREATE TABLE AS and REFRESH return an OID
Other DDL commands are already returning the OID, which is required for
future additional event trigger work.  This is merely making these
commands in line with the rest of utility command support.
2014-08-25 15:32:18 -04:00
Alvaro Herrera f41872d0c1 Implement ALTER TABLE .. SET LOGGED / UNLOGGED
This enables changing permanent (logged) tables to unlogged and
vice-versa.

(Docs for ALTER TABLE / SET TABLESPACE got shuffled in an order that
hopefully makes more sense than the original.)

Author: Fabrízio de Royes Mello
Reviewed by: Christoph Berg, Andres Freund, Thom Brown
Some tweaking by Álvaro Herrera
2014-08-22 14:27:00 -04:00
Stephen Frost 3c4cf08087 Rework 'MOVE ALL' to 'ALTER .. ALL IN TABLESPACE'
As 'ALTER TABLESPACE .. MOVE ALL' really didn't change the tablespace
but instead changed objects inside tablespaces, it made sense to
rework the syntax and supporting functions to operate under the
'ALTER (TABLE|INDEX|MATERIALIZED VIEW)' syntax and to be in
tablecmds.c.

Pointed out by Alvaro, who also suggested the new syntax.

Back-patch to 9.4.
2014-08-21 19:06:17 -04:00
Tom Lane 59efda3e50 Implement IMPORT FOREIGN SCHEMA.
This command provides an automated way to create foreign table definitions
that match remote tables, thereby reducing tedium and chances for error.
In this patch, we provide the necessary core-server infrastructure and
implement the feature fully in the postgres_fdw foreign-data wrapper.
Other wrappers will throw a "feature not supported" error until/unless
they are updated.

Ronan Dunklau and Michael Paquier, additional work by me
2014-07-10 15:01:43 -04:00
Heikki Linnakangas 0ef0b6784c Change the signature of rm_desc so that it's passed a XLogRecord.
Just feels more natural, and is more consistent with rm_redo.
2014-06-14 10:46:48 +03:00
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
Noah Misch 7cbe57c34d Offer triggers on foreign tables.
This covers all the SQL-standard trigger types supported for regular
tables; it does not cover constraint triggers.  The approach for
acquiring the old row mirrors that for view INSTEAD OF triggers.  For
AFTER ROW triggers, we spool the foreign tuples to a tuplestore.

This changes the FDW API contract; when deciding which columns to
populate in the slot returned from data modification callbacks, writable
FDWs will need to check for AFTER ROW triggers in addition to checking
for a RETURNING clause.

In support of the feature addition, refactor the TriggerFlags bits and
the assembly of old tuples in ModifyTable.

Ronan Dunklau, reviewed by KaiGai Kohei; some additional hacking by me.
2014-03-23 02:16:34 -04:00
Robert Haas b89e151054 Introduce logical decoding.
This feature, building on previous commits, allows the write-ahead log
stream to be decoded into a series of logical changes; that is,
inserts, updates, and deletes and the transactions which contain them.
It is capable of handling decoding even across changes to the schema
of the effected tables.  The output format is controlled by a
so-called "output plugin"; an example is included.  To make use of
this in a real replication system, the output plugin will need to be
modified to produce output in the format appropriate to that system,
and to perform filtering.

Currently, information can be extracted from the logical decoding
system only via SQL; future commits will add the ability to stream
changes via walsender.

Andres Freund, with review and other contributions from many other
people, including Álvaro Herrera, Abhijit Menon-Sen, Peter Gheogegan,
Kevin Grittner, Robert Haas, Heikki Linnakangas, Fujii Masao, Abhijit
Menon-Sen, Michael Paquier, Simon Riggs, Craig Ringer, and Steve
Singer.
2014-03-03 16:32:18 -05:00
Robert Haas 5f173040e3 Avoid repeated name lookups during table and index DDL.
If the name lookups come to different conclusions due to concurrent
activity, we might perform some parts of the DDL on a different table
than other parts.  At least in the case of CREATE INDEX, this can be
used to cause the permissions checks to be performed against a
different table than the index creation, allowing for a privilege
escalation attack.

This changes the calling convention for DefineIndex, CreateTrigger,
transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible
(in 9.2 and newer), and AlterTable (in 9.1 and older).  In addition,
CheckRelationOwnership is removed in 9.2 and newer and the calling
convention is changed in older branches.  A field has also been added
to the Constraint node (FkConstraint in 8.4).  Third-party code calling
these functions or using the Constraint node will require updating.

Report by Andres Freund.  Patch by Robert Haas and Andres Freund,
reviewed by Tom Lane.

Security: CVE-2014-0062
2014-02-17 09:33:31 -05:00
Alvaro Herrera 801c2dc72c Separate multixact freezing parameters from xid's
Previously we were piggybacking on transaction ID parameters to freeze
multixacts; but since there isn't necessarily any relationship between
rates of Xid and multixact consumption, this turns out not to be a good
idea.

Therefore, we now have multixact-specific freezing parameters:

vacuum_multixact_freeze_min_age: when to remove multis as we come across
them in vacuum (default to 5 million, i.e. early in comparison to Xid's
default of 50 million)

vacuum_multixact_freeze_table_age: when to force whole-table scans
instead of scanning only the pages marked as not all visible in
visibility map (default to 150 million, same as for Xids).  Whichever of
both which reaches the 150 million mark earlier will cause a whole-table
scan.

autovacuum_multixact_freeze_max_age: when for cause emergency,
uninterruptible whole-table scans (default to 400 million, double as
that for Xids).  This means there shouldn't be more frequent emergency
vacuuming than previously, unless multixacts are being used very
rapidly.

Backpatch to 9.3 where multixacts were made to persist enough to require
freezing.  To avoid an ABI break in 9.3, VacuumStmt has a couple of
fields in an unnatural place, and StdRdOptions is split in two so that
the newly added fields can go at the end.

Patch by me, reviewed by Robert Haas, with additional input from Andres
Freund and Tom Lane.
2014-02-13 19:36:31 -03:00
Robert Haas 9347baa5bb Include planning time in EXPLAIN ANALYZE output.
This doesn't work for prepared queries, but it's not too easy to get
the information in that case and there's some debate as to exactly
what the right thing to measure is, so just do this for now.

Andreas Karlsson, with slight doc changes by me.
2014-01-29 16:09:15 -05:00
Stephen Frost fbe19ee3b8 ALTER TABLESPACE ... MOVE ... OWNED BY
Add the ability to specify the objects to move by who those objects are
owned by (as relowner) and change ALL to mean ALL objects.  This
makes the command always operate against a well-defined set of objects
and not have the objects-to-be-moved based on the role of the user
running the command.

Per discussion with Simon and Tom.
2014-01-23 23:52:40 -05:00
Alvaro Herrera d2458e3b20 Expose a routine to print triggers during EXPLAIN ANALYZE
This is so that auto_explain can use it.

Kyotaro HORIGUCHI
2014-01-20 17:13:47 -03:00
Stephen Frost 76e91b38ba Add ALTER TABLESPACE ... MOVE command
This adds a 'MOVE' sub-command to ALTER TABLESPACE which allows moving sets of
objects from one tablespace to another.  This can be extremely handy and avoids
a lot of error-prone scripting.  ALTER TABLESPACE ... MOVE will only move
objects the user owns, will notify the user if no objects were found, and can
be used to move ALL objects or specific types of objects (TABLES, INDEXES, or
MATERIALIZED VIEWS).
2014-01-18 18:56:40 -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 3cff1879f8 Aggressively freeze tables when CLUSTER or VACUUM FULL rewrites them.
We haven't wanted to do this in the past on the grounds that in rare
cases the original xmin value will be needed for forensic purposes, but
commit 37484ad2aa removes that objection,
so now we can.

Per extensive discussion, among many people, on pgsql-hackers.
2014-01-02 15:15:51 -05:00
Tom Lane 8d65da1f01 Support ordered-set (WITHIN GROUP) aggregates.
This patch introduces generic support for ordered-set and hypothetical-set
aggregate functions, as well as implementations of the instances defined in
SQL:2008 (percentile_cont(), percentile_disc(), rank(), dense_rank(),
percent_rank(), cume_dist()).  We also added mode() though it is not in the
spec, as well as versions of percentile_cont() and percentile_disc() that
can compute multiple percentile values in one pass over the data.

Unlike the original submission, this patch puts full control of the sorting
process in the hands of the aggregate's support functions.  To allow the
support functions to find out how they're supposed to sort, a new API
function AggGetAggref() is added to nodeAgg.c.  This allows retrieval of
the aggregate call's Aggref node, which may have other uses beyond the
immediate need.  There is also support for ordered-set aggregates to
install cleanup callback functions, so that they can be sure that
infrastructure such as tuplesort objects gets cleaned up.

In passing, make some fixes in the recently-added support for variadic
aggregates, and make some editorial adjustments in the recent FILTER
additions for aggregates.  Also, simplify use of IsBinaryCoercible() by
allowing it to succeed whenever the target type is ANY or ANYELEMENT.
It was inconsistent that it dealt with other polymorphic target types
but not these.

Atri Sharma and Andrew Gierth; reviewed by Pavel Stehule and Vik Fearing,
and rather heavily editorialized upon by Tom Lane
2013-12-23 16:11:35 -05:00
Alvaro Herrera f54106f77e Fix full-table-vacuum request mechanism for MultiXactIds
While autovacuum dutifully launched anti-multixact-wraparound vacuums
when the multixact "age" was reached, the vacuum code was not aware that
it needed to make them be full table vacuums.  As the resulting
partial-table vacuums aren't capable of actually increasing relminmxid,
autovacuum continued to launch anti-wraparound vacuums that didn't have
the intended effect, until age of relfrozenxid caused the vacuum to
finally be a full table one via vacuum_freeze_table_age.

To fix, introduce logic for multixacts similar to that for plain
TransactionIds, using the same GUCs.

Backpatch to 9.3, where permanent MultiXactIds were introduced.

Andres Freund, some cleanup by Álvaro
2013-11-29 21:47:13 -03:00
Tom Lane 6cb86143e8 Allow aggregates to provide estimates of their transition state data size.
Formerly the planner had a hard-wired rule of thumb for guessing the amount
of space consumed by an aggregate function's transition state data.  This
estimate is critical to deciding whether it's OK to use hash aggregation,
and in many situations the built-in estimate isn't very good.  This patch
adds a column to pg_aggregate wherein a per-aggregate estimate can be
provided, overriding the planner's default, and infrastructure for setting
the column via CREATE AGGREGATE.

It may be that additional smarts will be required in future, perhaps even
a per-aggregate estimation function.  But this is already a step forward.

This is extracted from a larger patch to improve the performance of numeric
and int8 aggregates.  I (tgl) thought it was worth reviewing and committing
this infrastructure separately.  In this commit, all built-in aggregates
are given aggtransspace = 0, so no behavior should change.

Hadi Moshayedi, reviewed by Pavel Stehule and Tomas Vondra
2013-11-16 16:03:40 -05:00
Robert Haas d90ced8bb2 Add DISCARD SEQUENCES command.
DISCARD ALL will now discard cached sequence information, as well.

Fabrízio de Royes Mello, reviewed by Zoltán Böszörményi, with some
further tweaks by me.
2013-10-03 16:23:31 -04:00
Alvaro Herrera dd778e9d88 Rename various "freeze multixact" variables
It seems to make more sense to use "cutoff multixact" terminology
throughout the backend code; "freeze" is associated with replacing of an
Xid with FrozenTransactionId, which is not what we do for MultiXactIds.

Andres Freund
Some adjustments by Álvaro Herrera
2013-09-16 15:47:31 -03:00
Tom Lane 0d3f4406df Allow aggregate functions to be VARIADIC.
There's no inherent reason why an aggregate function can't be variadic
(even VARIADIC ANY) if its transition function can handle the case.
Indeed, this patch to add the feature touches none of the planner or
executor, and little of the parser; the main missing stuff was DDL and
pg_dump support.

It is true that variadic aggregates can create the same sort of ambiguity
about parameters versus ORDER BY keys that was complained of when we
(briefly) had both one- and two-argument forms of string_agg().  However,
the policy formed in response to that discussion only said that we'd not
create any built-in aggregates with varying numbers of arguments, not that
we shouldn't allow users to do it.  So the logical extension of that is
we can allow users to make variadic aggregates as long as we're wary about
shipping any such in core.

In passing, this patch allows aggregate function arguments to be named, to
the extent of remembering the names in pg_proc and dumping them in pg_dump.
You can't yet call an aggregate using named-parameter notation.  That seems
like a likely future extension, but it'll take some work, and it's not what
this patch is really about.  Likewise, there's still some work needed to
make window functions handle VARIADIC fully, but I left that for another
day.

initdb forced because of new aggvariadic field in Aggref parse nodes.
2013-09-03 17:08:46 -04:00
Stephen Frost 4cbe3ac3e8 WITH CHECK OPTION support for auto-updatable VIEWs
For simple views which are automatically updatable, this patch allows
the user to specify what level of checking should be done on records
being inserted or updated.  For 'LOCAL CHECK', new tuples are validated
against the conditionals of the view they are being inserted into, while
for 'CASCADED CHECK' the new tuples are validated against the
conditionals for all views involved (from the top down).

This option is part of the SQL specification.

Dean Rasheed, reviewed by Pavel Stehule
2013-07-18 17:10:16 -04:00
Kevin Grittner cc1965a99b Add support for REFRESH MATERIALIZED VIEW CONCURRENTLY.
This allows reads to continue without any blocking while a REFRESH
runs.  The new data appears atomically as part of transaction
commit.

Review questioned the Assert that a matview was not a system
relation.  This will be addressed separately.

Reviewed by Hitoshi Harada, Robert Haas, Andres Freund.
Merged after review with security patch f3ab5d4.
2013-07-16 12:55:44 -05:00
Noah Misch 813895e4ac Don't pass oidvector by value.
Since the structure ends with a flexible array, doing so truncates any
vector having more than one element.  New in 9.3, so no back-patch.
2013-06-12 19:50:37 -04:00
Bruce Momjian 9af4159fce pgindent run for release 9.3
This is the first run of the Perl-based pgindent script.  Also update
pgindent instructions.
2013-05-29 16:58:43 -04:00
Tom Lane 1d6c72a55b Move materialized views' is-populated status into their pg_class entries.
Previously this state was represented by whether the view's disk file had
zero or nonzero size, which is problematic for numerous reasons, since it's
breaking a fundamental assumption about heap storage.  This was done to
allow unlogged matviews to revert to unpopulated status after a crash
despite our lack of any ability to update catalog entries post-crash.
However, this poses enough risk of future problems that it seems better to
not support unlogged matviews until we can find another way.  Accordingly,
revert that choice as well as a number of existing kluges forced by it
in favor of creating a pg_class.relispopulated flag column.
2013-05-06 13:27:22 -04:00
Tom Lane 0b33790421 Clean up the mess around EXPLAIN and materialized views.
Revert the matview-related changes in explain.c's API, as per recent
complaint from Robert Haas.  The reason for these appears to have been
principally some ill-considered choices around having intorel_startup do
what ought to be parse-time checking, plus a poor arrangement for passing
it the view parsetree it needs to store into pg_rewrite when creating a
materialized view.  Do the latter by having parse analysis stick a copy
into the IntoClause, instead of doing it at runtime.  (On the whole,
I seriously question the choice to represent CREATE MATERIALIZED VIEW as a
variant of SELECT INTO/CREATE TABLE AS, because that means injecting even
more complexity into what was already a horrid legacy kluge.  However,
I didn't go so far as to rethink that choice ... yet.)

I also moved several error checks into matview parse analysis, and
made the check for external Params in a matview more accurate.

In passing, clean things up a bit more around interpretOidsOption(),
and fix things so that we can use that to force no-oids for views,
sequences, etc, thereby eliminating the need to cons up "oids = false"
options when creating them.

catversion bump due to change in IntoClause.  (I wonder though if we
really need readfuncs/outfuncs support for IntoClause anymore.)
2013-04-12 19:25:31 -04:00
Alvaro Herrera 6a76edb188 Fix confusion between ObjectType and ObjectClass
Per report by Will Leinweber and Peter Eisentraut
2013-04-11 11:59:47 -03:00
Kevin Grittner 52e6e33ab4 Create a distinction between a populated matview and a scannable one.
The intent was that being populated would, long term, be just one
of the conditions which could affect whether a matview was
scannable; being populated should be necessary but not always
sufficient to scan the relation.  Since only CREATE and REFRESH
currently determine the scannability, names and comments
accidentally conflated these concepts, leading to confusion.

Also add missing locking for the SQL function which allows a
test for scannability, and fix a modularity violatiion.

Per complaints from Tom Lane, although its not clear that these
will satisfy his concerns.  Hopefully this will at least better
frame the discussion.
2013-04-09 13:02:49 -05:00
Robert Haas 0bf42a5f3b Adjust ExplainOneQuery_hook_type to take a DestReceiver argument.
The materialized views patch adjusted ExplainOneQuery to take an
additional DestReceiver argument, but failed to add a matching
argument to the definition of ExplainOneQuery_hook.  This is a
problem for users of the hook that want to call ExplainOnePlan.
Fix by adding the missing argument.
2013-04-09 10:25:08 -04:00
Alvaro Herrera 473ab40c8b Add sql_drop event for event triggers
This event takes place just before ddl_command_end, and is fired if and
only if at least one object has been dropped by the command.  (For
instance, DROP TABLE IF EXISTS of a table that does not in fact exist
will not lead to such a trigger firing).  Commands that drop multiple
objects (such as DROP SCHEMA or DROP OWNED BY) will cause a single event
to fire.  Some firings might be surprising, such as
ALTER TABLE DROP COLUMN.

The trigger is fired after the drop has taken place, because that has
been deemed the safest design, to avoid exposing possibly-inconsistent
internal state (system catalogs as well as current transaction) to the
user function code.  This means that careful tracking of object
identification is required during the object removal phase.

Like other currently existing events, there is support for tag
filtering.

To support the new event, add a new pg_event_trigger_dropped_objects()
set-returning function, which returns a set of rows comprising the
objects affected by the command.  This is to be used within the user
function code, and is mostly modelled after the recently introduced
pg_identify_object() function.

Catalog version bumped due to the new function.

Dimitri Fontaine and Álvaro Herrera
Review by Robert Haas, Tom Lane
2013-03-28 13:05:48 -03:00
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
Tom Lane e11cb8ba2c Fix missing #include in commands/matview.h.
It needs parsenodes.h to be compilable regardless of previous headers.
2013-03-06 18:21:05 -05:00
Kevin Grittner 3bf3ab8c56 Add a materialized view relations.
A materialized view has a rule just like a view and a heap and
other physical properties like a table.  The rule is only used to
populate the table, references in queries refer to the
materialized data.

This is a minimal implementation, but should still be useful in
many cases.  Currently data is only populated "on demand" by the
CREATE MATERIALIZED VIEW and REFRESH MATERIALIZED VIEW statements.
It is expected that future releases will add incremental updates
with various timings, and that a more refined concept of defining
what is "fresh" data will be developed.  At some point it may even
be possible to have queries use a materialized in place of
references to underlying tables, but that requires the other
above-mentioned features to be working first.

Much of the documentation work by Robert Haas.
Review by Noah Misch, Thom Brown, Robert Haas, Marko Tiikkaja
Security review by KaiGai Kohei, with a decision on how best to
implement sepgsql still pending.
2013-03-03 18:23:31 -06:00