Release 9.4.1Release Date2015-02-05
This release contains a variety of fixes from 9.4.0.
For information about new features in the 9.4 major release, see
.
Migration to Version 9.4.1
A dump/restore is not required for those running 9.4.X.
However, if you are a Windows user and are using the Norwegian
(Bokmål)> locale, manual action is needed after the upgrade to
replace any Norwegian (Bokmål)_Norway>
or norwegian-bokmal> locale names stored
in PostgreSQL> system catalogs with the plain-ASCII
alias Norwegian_Norway>. For details see
>
Changes
Fix buffer overruns in to_char()>
(Bruce Momjian)
When to_char()> processes a numeric formatting template
calling for a large number of digits, PostgreSQL>
would read past the end of a buffer. When processing a crafted
timestamp formatting template, PostgreSQL> would write
past the end of a buffer. Either case could crash the server.
We have not ruled out the possibility of attacks that lead to
privilege escalation, though they seem unlikely.
(CVE-2015-0241)
Fix buffer overrun in replacement *printf()> functions
(Tom Lane)
PostgreSQL> includes a replacement implementation
of printf> and related functions. This code will overrun
a stack buffer when formatting a floating point number (conversion
specifiers e>, E>, f>, F>,
g> or G>) with requested precision greater than
about 500. This will crash the server, and we have not ruled out the
possibility of attacks that lead to privilege escalation.
A database user can trigger such a buffer overrun through
the to_char()> SQL function. While that is the only
affected core PostgreSQL> functionality, extension
modules that use printf-family functions may be at risk as well.
This issue primarily affects PostgreSQL> on Windows.
PostgreSQL> uses the system implementation of these
functions where adequate, which it is on other modern platforms.
(CVE-2015-0242)
Fix buffer overruns in contrib/pgcrypto>
(Marko Tiikkaja, Noah Misch)
Errors in memory size tracking within the pgcrypto>
module permitted stack buffer overruns and improper dependence on the
contents of uninitialized memory. The buffer overrun cases can
crash the server, and we have not ruled out the possibility of
attacks that lead to privilege escalation.
(CVE-2015-0243)
Fix possible loss of frontend/backend protocol synchronization after
an error
(Heikki Linnakangas)
If any error occurred while the server was in the middle of reading a
protocol message from the client, it could lose synchronization and
incorrectly try to interpret part of the message's data as a new
protocol message. An attacker able to submit crafted binary data
within a command parameter might succeed in injecting his own SQL
commands this way. Statement timeout and query cancellation are the
most likely sources of errors triggering this scenario. Particularly
vulnerable are applications that use a timeout and also submit
arbitrary user-crafted data as binary query parameters. Disabling
statement timeout will reduce, but not eliminate, the risk of
exploit. Our thanks to Emil Lenngren for reporting this issue.
(CVE-2015-0244)
Fix information leak via constraint-violation error messages
(Stephen Frost)
Some server error messages show the values of columns that violate
a constraint, such as a unique constraint. If the user does not have
SELECT> privilege on all columns of the table, this could
mean exposing values that the user should not be able to see. Adjust
the code so that values are displayed only when they came from the SQL
command or could be selected by the user.
(CVE-2014-8161)
Lock down regression testing's temporary installations on Windows
(Noah Misch)
Use SSPI authentication to allow connections only from the OS user
who launched the test suite. This closes on Windows the same
vulnerability previously closed on other platforms, namely that other
users might be able to connect to the test postmaster.
(CVE-2014-0067)
Cope with the Windows locale named Norwegian (Bokmål)>
(Heikki Linnakangas)
Non-ASCII locale names are problematic since it's not clear what
encoding they should be represented in. Map the troublesome locale
name to a plain-ASCII alias, Norwegian_Norway>.
9.4.0 mapped the troublesome name to norwegian-bokmal>,
but that turns out not to work on all Windows configurations.
Norwegian_Norway> is now recommended instead.
Fix use-of-already-freed-memory problem in EvalPlanQual processing
(Tom Lane)
In READ COMMITTED> mode, queries that lock or update
recently-updated rows could crash as a result of this bug.
Avoid possible deadlock while trying to acquire tuple locks
in EvalPlanQual processing (Álvaro Herrera, Mark Kirkwood)
Fix failure to wait when a transaction tries to acquire a FOR
NO KEY EXCLUSIVE> tuple lock, while multiple other transactions
currently hold FOR SHARE> locks (Álvaro Herrera)
Improve performance of EXPLAIN> with large range tables
(Tom Lane)
Fix jsonb> Unicode escape processing, and in consequence
disallow \u0000> (Tom Lane)
Previously, the JSON Unicode escape \u0000> was accepted
and was stored as those six characters; but that is indistinguishable
from what is stored for the input \\u0000>, resulting in
ambiguity. Moreover, in cases where de-escaped textual output is
expected, such as the ->>> operator, the sequence was
printed as \u0000>, which does not meet the expectation
that JSON escaping would be removed. (Consistent behavior would
require emitting a zero byte, but PostgreSQL> does not
support zero bytes embedded in text strings.) 9.4.0 included an
ill-advised attempt to improve this situation by adjusting JSON output
conversion rules; but of course that could not fix the fundamental
ambiguity, and it turned out to break other usages of Unicode escape
sequences. Revert that, and to avoid the core problem,
reject \u0000> in jsonb> input.
If a jsonb> column contains a \u0000> value stored
with 9.4.0, it will henceforth read out as though it
were \\u0000>, which is the other valid interpretation of
the data stored by 9.4.0 for this case.
The json> type did not have the storage-ambiguity problem, but
it did have the problem of inconsistent de-escaped textual output.
Therefore \u0000> will now also be rejected
in json> values when conversion to de-escaped form is
required. This change does not break the ability to
store \u0000> in json> columns so long as no
processing is done on the values. This is exactly parallel to the
cases in which non-ASCII Unicode escapes are allowed when the database
encoding is not UTF8.
Fix namespace handling in xpath()> (Ali Akbar)
Previously, the xml> value resulting from
an xpath()> call would not have namespace declarations if
the namespace declarations were attached to an ancestor element in the
input xml> value, rather than to the specific element being
returned. Propagate the ancestral declaration so that the result is
correct when considered in isolation.
Fix assorted oversights in range-operator selectivity estimation
(Emre Hasegeli)
This patch fixes corner-case unexpected operator NNNN> planner
errors, and improves the selectivity estimates for some other cases.
Revert unintended reduction in maximum size of a GIN index item
(Heikki Linnakangas)
9.4.0 could fail with index row size exceeds maximum> errors
for data that previous versions would accept.
Fix query-duration memory leak during repeated GIN index rescans
(Heikki Linnakangas)
Fix possible crash when using
nonzero gin_fuzzy_search_limit> (Heikki Linnakangas)
Assorted fixes for logical decoding (Andres Freund)
Fix incorrect replay of WAL parameter change records that report
changes in the wal_log_hints> setting (Petr Jelinek)
Change pgstat wait timeout> warning message to be LOG level,
and rephrase it to be more understandable (Tom Lane)
This message was originally thought to be essentially a can't-happen
case, but it occurs often enough on our slower buildfarm members to be
a nuisance. Reduce it to LOG level, and expend a bit more effort on
the wording: it now reads using stale statistics instead of
current ones because stats collector is not responding>.
Warn if OS X's setlocale()> starts an unwanted extra
thread inside the postmaster (Noah Misch)
Fix libpq>'s behavior when /etc/passwd>
isn't readable (Tom Lane)
While doing PQsetdbLogin()>, libpq>
attempts to ascertain the user's operating system name, which on most
Unix platforms involves reading /etc/passwd>. As of 9.4,
failure to do that was treated as a hard error. Restore the previous
behavior, which was to fail only if the application does not provide a
database role name to connect as. This supports operation in chroot
environments that lack an /etc/passwd> file.
Improve consistency of parsing of psql>'s special
variables (Tom Lane)
Allow variant spellings of on> and off> (such
as 1>/0>) for ECHO_HIDDEN>
and ON_ERROR_ROLLBACK>. Report a warning for unrecognized
values for COMP_KEYWORD_CASE>, ECHO>,
ECHO_HIDDEN>, HISTCONTROL>,
ON_ERROR_ROLLBACK>, and VERBOSITY>. Recognize
all values for all these variables case-insensitively; previously
there was a mishmash of case-sensitive and case-insensitive behaviors.
Fix pg_dump> to handle comments on event triggers
without failing (Tom Lane)
Allow parallel pg_dump> to
use
Prevent WAL files created by pg_basebackup -x/-X> from
being archived again when the standby is promoted (Andres Freund)
Handle unexpected query results, especially NULLs, safely in
contrib/tablefunc>'s connectby()>
(Michael Paquier)
connectby()> previously crashed if it encountered a NULL
key value. It now prints that row but doesn't recurse further.
Numerous cleanups of warnings from Coverity static code analyzer
(Andres Freund, Tatsuo Ishii, Marko Kreen, Tom Lane, Michael Paquier)
These changes are mostly cosmetic but in some cases fix corner-case
bugs, for example a crash rather than a proper error report after an
out-of-memory failure. None are believed to represent security
issues.
Allow CFLAGS> from configure>'s environment
to override automatically-supplied CFLAGS> (Tom Lane)
Previously, configure> would add any switches that it
chose of its own accord to the end of the
user-specified CFLAGS> string. Since most compilers
process switches left-to-right, this meant that configure's choices
would override the user-specified flags in case of conflicts. That
should work the other way around, so adjust the logic to put the
user's string at the end not the beginning.
Make pg_regress> remove any temporary installation it
created upon successful exit (Tom Lane)
This results in a very substantial reduction in disk space usage
during make check-world>, since that sequence involves
creation of numerous temporary installations.
Add CST (China Standard Time) to our lists of timezone abbreviations
(Tom Lane)
Update time zone data files to tzdata> release 2015a
for DST law changes in Chile and Mexico, plus historical changes in
Iceland.
Release 9.4Release Date2014-12-18Overview
Major enhancements in PostgreSQL> 9.4 include:
Add jsonb>, a more
capable and efficient data type for storing JSON> data
Add new SQL> command
for changing postgresql.conf> configuration file entries
Reduce lock strength for some
commands
Allow materialized views>
to be refreshed without blocking concurrent reads
Add support for logical decoding>
of WAL data, to allow database changes to be streamed out in a
customizable format
Allow background worker processes>
to be dynamically registered, started and terminated
The above items are explained in more detail in the sections below.
Migration to Version 9.4
A dump/restore using , or use
of , is required for those wishing to migrate
data from any previous release.
Version 9.4 contains a number of changes that may affect compatibility
with previous releases. Observe the following incompatibilities:
Tighten checks for multidimensional array input (Bruce Momjian)
Previously, an input array string that started with a single-element
sub-array could later contain multi-element sub-arrays,
e.g. '{{1}, {2,3}}'::int[]> would be accepted.
When converting values of type date>, timestamp>
or timestamptz>
to JSON, render the
values in a format compliant with ISO 8601 (Andrew Dunstan)
Previously such values were rendered according to the current
setting; but many JSON processors
require timestamps to be in ISO 8601 format. If necessary, the
previous behavior can be obtained by explicitly casting the datetime
value to text> before passing it to the JSON conversion
function.
The json#>> text[]> path extraction operator now
returns its lefthand input, not NULL, if the array is empty (Tom Lane)
This is consistent with the notion that this represents zero
applications of the simple field/element extraction
operator ->>. Similarly, json#>>> text[]> with an empty array merely
coerces its lefthand input to text.
Corner cases in
the JSON
field/element/path extraction operators now return NULL rather
than raising an error (Tom Lane)
For example, applying field extraction to a JSON array now yields NULL
not an error. This is more consistent (since some comparable cases such
as no-such-field already returned NULL), and it makes it safe to create
expression indexes that use these operators, since they will now not
throw errors for any valid JSON input.
Cause consecutive whitespace in to_timestamp()>
and to_date()> format strings to consume a corresponding
number of characters in the input string (whitespace or not), then
conditionally consume adjacent whitespace, if not in FX>
mode (Jeevan Chalke)
Previously, consecutive whitespace characters in a non-FX>
format string behaved like a single whitespace character and consumed
all adjacent whitespace in the input string. For example, previously
a format string of three spaces would consume only the first space in
' 12'>, but it will now consume all three characters.
Fix ts_rank_cd()>
to ignore stripped lexemes (Alex Hill)
Previously, stripped lexemes were treated as if they had a default
location, producing a rank of dubious usefulness.
For functions declared to
take VARIADIC
"any">, an actual parameter marked as VARIADIC>
must be of a determinable array type (Pavel Stehule)
Such parameters can no longer be written as an undecorated string
literal or NULL>; a cast to an appropriate array data type
will now be required. Note that this does not affect parameters not
marked VARIADIC>.
Ensure that whole-row variables expose the expected column names
to functions that pay attention to column names within composite
arguments (Tom Lane)
Constructs like row_to_json(tab.*)> now always emit column
names that match the column aliases visible for table tab>
at the point of the call. In previous releases the emitted column
names would sometimes be the table's actual column names regardless
of any aliases assigned in the query.
now also discards sequence-related state
(Fabrízio de Royes Mello, Robert Haas)
Rename EXPLAIN
ANALYZE>'s total runtime output
to execution time (Tom Lane)
Now that planning time is also reported, the previous name was
confusing.
SHOW TIME ZONE> now
outputs simple numeric UTC offsets in POSIX> timezone
format (Tom Lane)
Previously, such timezone settings were displayed as interval> values.
The new output is properly interpreted by SET TIME ZONE>
when passed as a simple string, whereas the old output required
special treatment to be re-parsed correctly.
Foreign data wrappers that support updating foreign tables must
consider the possible presence of AFTER ROW> triggers
(Noah Misch)
When an AFTER ROW> trigger is present, all columns of the
table must be returned by updating actions, since the trigger might
inspect any or all of them. Previously, foreign tables never had
triggers, so the FDW might optimize away fetching columns not mentioned
in the RETURNING> clause (if any).
Prevent CHECK>
constraints from referencing system columns, except
tableoid> (Amit Kapila)
Previously such check constraints were allowed, but they would often
cause errors during restores.
Use the last specified recovery
target parameter if multiple target parameters are specified
(Heikki Linnakangas)
Previously, there was an undocumented precedence order among
the recovery_target_xxx> parameters.
On Windows, automatically preserve quotes in command strings supplied
by the user (Heikki Linnakangas)
User commands that did their own quote preservation might need
adjustment. This is likely to be an issue for commands used in
, ,
and COPY TO/FROM PROGRAM>.
Remove catalog column pg_class.reltoastidxid>
(Michael Paquier)
Remove catalog column pg_rewrite.ev_attr>
(Kevin Grittner)
Per-column rules have not been supported since
PostgreSQL> 7.3.
Remove native support for Kerberos> authentication
(
The supported way to use Kerberos> authentication is
with GSSAPI>. The native code has been deprecated since
PostgreSQL> 8.3.
In PL/Python>, handle domains over arrays like the
underlying array type (Rodolfo Campero)
Previously such values were treated as strings.
Make libpq's PQconnectdbParams()>
and PQpingParams()>
functions process zero-length strings as defaults (Adrian
Vondendriesch)
Previously, these functions treated zero-length string values as
selecting the default in only some cases.
Change empty arrays returned by the module
to be zero-dimensional arrays (Bruce Momjian)
Previously, empty arrays were returned as zero-length one-dimensional
arrays, whose text representation looked the same as zero-dimensional
arrays ({}>), but they acted differently in array
operations. intarray>'s behavior in this area now
matches the built-in array operators.
now uses
Previously this option was spelled Changes
Below you will find a detailed account of the changes between
PostgreSQL 9.4 and the previous major
release.
Server
Allow background worker processes
to be dynamically registered, started and terminated (Robert Haas)
The new worker_spi> module shows an example of use
of this feature.
Allow dynamic allocation of shared memory segments (Robert Haas,
Amit Kapila)
This feature is illustrated in the test_shm_mq
module.
During crash recovery or immediate shutdown, send uncatchable
termination signals (SIGKILL>) to child processes
that do not shut down promptly (MauMau, Álvaro Herrera)
This reduces the likelihood of leaving orphaned child processes
behind after shutdown, as well
as ensuring that crash recovery can proceed if some child processes
have become stuck>.
Improve randomness of the database system identifier (Tom Lane)
Make properly report dead but
not-yet-removable rows to the statistics collector (Hari Babu)
Previously these were reported as live rows.
Indexes
Reduce GIN> index size
(Alexander Korotkov, Heikki Linnakangas)
Indexes upgraded via will work fine
but will still be in the old, larger GIN> format.
Use to recreate old GIN indexes in the
new format.
Improve speed of multi-key GIN> lookups (Alexander Korotkov,
Heikki Linnakangas)
Add GiST> index support
for inet> and
cidr> data types
(Emre Hasegeli)
Such indexes improve subnet and supernet
lookups and ordering comparisons.
Fix rare race condition in B-tree page deletion (Heikki Linnakangas)
Make the handling of interrupted B-tree page splits more robust
(Heikki Linnakangas)
General Performance
Allow multiple backends to insert
into WAL> buffers
concurrently (Heikki Linnakangas)
This improves parallel write performance.
Conditionally write only the modified portion of updated rows to
WAL> (Amit Kapila)
Improve performance of aggregate functions used as window functions
(David Rowley, Florian Pflug, Tom Lane)
Improve speed of aggregates that
use numeric> state
values (Hadi Moshayedi)
Attempt to freeze
tuples when tables are rewritten with or VACUUM FULL> (Robert Haas,
Andres Freund)
This can avoid the need to freeze the tuples in the future.
Improve speed of with default nextval()>
columns (Simon Riggs)
Improve speed of accessing many different sequences in the same session
(David Rowley)
Raise hard limit on the number of tuples held in memory during sorting
and B-tree index builds (Noah Misch)
Reduce memory allocated by PL/pgSQL>
blocks (Tom Lane)
Make the planner more aggressive about extracting restriction clauses
from mixed AND>/OR> clauses (Tom Lane)
Disallow pushing volatile WHERE> clauses down
into DISTINCT> subqueries (Tom Lane)
Pushing down a WHERE> clause can produce a more
efficient plan overall, but at the cost of evaluating the clause
more often than is implied by the text of the query; so don't do it
if the clause contains any volatile functions.
Auto-resize the catalog caches (Heikki Linnakangas)
This reduces memory consumption for sessions accessing only a few
tables, and improves performance for sessions accessing many tables.
Monitoring
Add system view to
report WAL> archiver activity
(Gabriele Bartolini)
Add n_mod_since_analyze> columns to
and related system views
(Mark Kirkwood)
These columns expose the system's estimate of the number of changed
tuples since the table's last . This
estimate drives decisions about when to auto-analyze.
Add backend_xid> and backend_xmin>
columns to the system view ,
and a backend_xmin> column to
(Christian Kruse)
SSL>
Add support for SSL> ECDH> key exchange
(Marko Kreen)
This allows use of Elliptic Curve keys for server authentication.
Such keys are faster and have better security than RSA>
keys. The new configuration parameter
controls which curve is used for ECDH>.
Improve the default setting
(Marko Kreen)
By default, the server not the client now controls the preference
order of SSL> ciphers
(Marko Kreen)
Previously, the order specified by
was usually ignored in favor of client-side defaults, which are not
configurable in most PostgreSQL> clients. If
desired, the old behavior can be restored via the new configuration
parameter .
Make show SSL>
encryption information (Andreas Kunert)
Improve SSL> renegotiation handling (Álvaro
Herrera)
Server Settings
Add new SQL> command
for changing postgresql.conf> configuration file entries
(Amit Kapila)
Previously such settings could only be changed by manually
editing postgresql.conf>.
Add configuration parameter
to control the amount of memory used by autovacuum workers
(Peter Geoghegan)
Add parameter to allow using huge
memory pages on Linux (Christian Kruse, Richard Poole, Abhijit
Menon-Sen)
This can improve performance on large-memory systems.
Add parameter
to limit the number of background workers (Robert Haas)
This is helpful in configuring a standby server to have the
required number of worker processes (the same as the primary).
Add superuser-only
parameter to load libraries at session start (Peter Eisentraut)
In contrast to , this
parameter can load any shared library, not just those in
the $libdir/plugins> directory.
Add parameter to enable WAL
logging of hint-bit changes (Sawada Masahiko)
Hint bit changes are not normally logged, except when checksums are
enabled. This is useful for external tools
like pg_rewind>.
Increase the default settings of
and by four times (Bruce
Momjian)
The new defaults are 4MB and 64MB respectively.
Increase the default setting of
to 4GB (Bruce Momjian, Tom Lane)
Allow printf-style space padding to be
specified in (David Rowley)
Allow terabyte units (TB>) to be used when specifying
configuration variable values (Simon Riggs)
Show PID>s of lock holders and waiters and improve
information about relations in
log messages (Christian Kruse)
Reduce server logging level when loading shared libraries (Peter
Geoghegan)
The previous level was LOG>, which was too verbose
for libraries loaded per-session.
On Windows, make SQL_ASCII>-encoded databases and server
processes (e.g., ) emit messages in
the character encoding of the server's Windows user locale
(Alexander Law, Noah Misch)
Previously these messages were output in the Windows
ANSI> code page.
Replication and Recovery
Add replication
slots to coordinate activity on streaming standbys with the
node they are streaming from (Andres Freund, Robert Haas)
Replication slots allow preservation of resources like
WAL> files on the primary until they are no longer
needed by standby servers.
Add recovery parameter
to delay replication (Robert Haas, Fabrízio de Royes Mello,
Simon Riggs)
Delaying replay on standby servers can be useful for recovering
from user errors.
Add
option
Improve recovery target processing (Heikki Linnakangas)
The timestamp reported
by pg_last_xact_replay_timestamp()>
now reflects already-committed records, not transactions about to
be committed. Recovering to a restore point now replays the restore
point, rather than stopping just before the restore point.
pg_switch_xlog()>
now clears any unused trailing space in the old WAL> file
(Heikki Linnakangas)
This improves the compression ratio for WAL> files.
Report failure return codes from external recovery commands>
(Peter Eisentraut)
Reduce spinlock contention during WAL> replay (Heikki
Linnakangas)
Write WAL> records of running transactions more
frequently (Andres Freund)
This allows standby servers to start faster and clean up resources
more aggressively.
Logical Decoding>
Logical decoding allows database changes to be streamed in a
configurable format. The data is read from
the WAL> and transformed into the
desired target format. To implement this feature, the following changes
were made:
Add support for logical decoding>
of WAL data, to allow database changes to be streamed out in a
customizable format
(Andres Freund)
Add new setting
Add table-level parameter REPLICA IDENTITY>
to control logical replication (Andres Freund)
Add relation option
Add application to receive
logical-decoding data (Andres Freund)
Add module to illustrate logical
decoding at the SQL> level (Andres Freund)
Queries
Add WITH
ORDINALITY> syntax to number the rows returned from a
set-returning function in the FROM> clause
(Andrew Gierth, David Fetter)
This is particularly useful for functions like
unnest()>.
Add ROWS
FROM()> syntax to allow horizontal concatenation of
set-returning functions in the FROM> clause (Andrew Gierth)
Allow to have
an empty target list (Tom Lane)
This was added so that views that select from a table with zero
columns can be dumped and restored correctly.
Ensure that SELECT ... FOR UPDATE
NOWAIT> does not wait in corner cases involving
already-concurrently-updated tuples (Craig Ringer and Thomas Munro)
Utility Commands
Add DISCARD
SEQUENCES> command to discard cached sequence-related state
(Fabrízio de Royes Mello, Robert Haas)
DISCARD ALL> will now also discard such information.
Add FORCE NULL> option
to COPY FROM>, which
causes quoted strings matching the specified null string to be
converted to NULLs in CSV> mode (Ian Barwick, Michael
Paquier)
Without this option, only unquoted matching strings will be imported
as null values.
Issue warnings for commands used outside of transaction blocks
when they can have no effect (Bruce Momjian)
New warnings are issued for SET
LOCAL>, SET CONSTRAINTS>, SET TRANSACTION> and
ABORT> when used outside a transaction block.
Make EXPLAIN ANALYZE> show planning time (Andreas
Karlsson)
Make EXPLAIN> show the grouping columns in Agg and
Group nodes (Tom Lane)
Make EXPLAIN ANALYZE> show exact and lossy
block counts in bitmap heap scans (Etsuro Fujita)
Views
Allow a materialized view>
to be refreshed without blocking other sessions from reading the view
meanwhile (Kevin Grittner)
This is done with REFRESH MATERIALIZED
VIEW CONCURRENTLY>.
Allow views to be automatically
updated even if they contain some non-updatable columns
(Dean Rasheed)
Previously the presence of non-updatable output columns such as
expressions, literals, and function calls prevented automatic
updates. Now INSERT>s, UPDATE>s and
DELETE>s are supported, provided that they do not
attempt to assign new values to any of the non-updatable columns.
Allow control over whether INSERT>s and
UPDATE>s can add rows to an auto-updatable view that
would not appear in the view (Dean Rasheed)
This is controlled with the new
clause WITH CHECK OPTION>.
Allow security barrier views>
to be automatically updatable (Dean Rasheed)
Object Manipulation
Support triggers on foreign
tables> (Ronan Dunklau)
Allow moving groups of objects from one tablespace to another
using the ALL IN TABLESPACE ... SET TABLESPACE> form of
, , or
(Stephen Frost)
Allow changing foreign key constraint deferrability
via ... ALTER
CONSTRAINT> (Simon Riggs)
Reduce lock strength for some
commands
(Simon Riggs, Noah Misch, Robert Haas)
Specifically, VALIDATE CONSTRAINT>, CLUSTER
ON>, SET WITHOUT CLUSTER>, ALTER COLUMN
SET STATISTICS>, ALTER COLUMN> SET>
Allow tablespace options to be set
in (Vik Fearing)
Formerly these options could only be set
via .
Allow to define the estimated
size of the aggregate's transition state data (Hadi Moshayedi)
Proper use of this feature allows the planner to better estimate
how much memory will be used by aggregates.
Fix DROP IF EXISTS> to avoid errors for non-existent
objects in more cases (Pavel Stehule, Dean Rasheed)
Improve how system relations are identified (Andres Freund,
Robert Haas)
Previously, relations once moved into the pg_catalog>
schema could no longer be modified or dropped.
Data Types
Fully implement the line> data type (Peter
Eisentraut)
The line segment> data type (lseg>) has always been
fully supported. The previous line> data type (which was
enabled only via a compile-time option) is not binary or
dump-compatible with the new implementation.
Add pg_lsn>
data type to represent a WAL> log sequence number
(LSN>) (Robert Haas, Michael Paquier)
Allow single-point polygon>s to be converted
to circle>s
(Bruce Momjian)
Support time zone abbreviations that change UTC offset from time to
time (Tom Lane)
Previously, PostgreSQL> assumed that the UTC offset
associated with a time zone abbreviation (such as EST>)
never changes in the usage of any particular locale. However this
assumption fails in the real world, so introduce the ability for a
zone abbreviation to represent a UTC offset that sometimes changes.
Update the zone abbreviation definition files to make use of this
feature in timezone locales that have changed the UTC offset of their
abbreviations since 1970 (according to the IANA timezone database).
In such timezones, PostgreSQL> will now associate the
correct UTC offset with the abbreviation depending on the given date.
Allow 5+ digit years for non-ISO> timestamp> and
date> strings, where appropriate (Bruce Momjian)
Add checks for overflow/underflow of interval> values
(Bruce Momjian)
JSON>
Add jsonb>, a more
capable and efficient data type for storing JSON> data
(Oleg Bartunov, Teodor Sigaev, Alexander
Korotkov, Peter Geoghegan, Andrew Dunstan)
This new type allows faster access to values within a JSON
document, and faster and more useful indexing of JSON columns.
Scalar values in jsonb> documents are stored as appropriate
scalar SQL types, and the JSON document structure is pre-parsed
rather than being stored as text as in the original json>
data type.
Add new JSON functions to allow for the construction
of arbitrarily complex JSON trees (Andrew Dunstan, Laurence Rowe)
New functions include json_array_elements_text()>,
json_build_array()>, json_object()>,
json_object_agg()>, json_to_record()>,
and json_to_recordset()>.
Add json_typeof()>
to return the data type of a json> value (Andrew Tipton)
Functions
Add pg_sleep_for(interval)>
and pg_sleep_until(timestamp)> to specify
delays more flexibly (Vik Fearing, Julien Rouhaud)
The existing pg_sleep()> function only supports delays
specified in seconds.
Add cardinality()>
function for arrays (Marko Tiikkaja)
This returns the total number of elements in the array, or zero
for an array with no elements.
Add SQL> functions to allow large
object reads/writes at arbitrary offsets (Pavel Stehule)
Allow unnest()>
to take multiple arguments, which are individually unnested then
horizontally concatenated (Andrew Gierth)
Add functions to construct time>s, date>s,
timestamp>s, timestamptz>s, and interval>s
from individual values, rather than strings (Pavel Stehule)
These functions' names are prefixed with make_>,
e.g. make_date()>.
Make to_char()>'s
TZ> format specifier return a useful value for simple
numeric time zone offsets (Tom Lane)
Previously, to_char(CURRENT_TIMESTAMP, 'TZ')> returned
an empty string if the timezone> was set to a constant
like -4>.
Add timezone offset format specifier OF> to to_char()>
(Bruce Momjian)
Improve the random seed used for random()>
(Honza Horak)
Tighten validity checking for Unicode code points in chr(int)>
(Tom Lane)
This function now only accepts values that are valid UTF8 characters
according to RFC 3629.
System Information Functions
Add functions for looking up objects in pg_class>,
pg_proc>, pg_type>, and
pg_operator> that do not generate errors for
non-existent objects (Yugo Nagata, Nozomi Anzai,
Robert Haas)
For example, to_regclass()>
does a lookup in pg_class> similarly to
the regclass> input function, but it returns NULL for a
non-existent object instead of failing.
Add function pg_filenode_relation()>
to allow for more efficient lookup of relation names from filenodes
(Andres Freund)
Add parameter_default> column to information_schema.parameters>
view (Peter Eisentraut)
Make information_schema.schemata>
show all accessible schemas (Peter Eisentraut)
Previously it only showed schemas owned by the current user.
Aggregates
Add control over which rows are passed
into aggregate functions via the FILTER> clause
(David Fetter)
Support ordered-set (WITHIN GROUP>)
aggregates (Atri Sharma, Andrew Gierth, Tom Lane)
Add standard ordered-set aggregates percentile_cont()>,
percentile_disc()>, mode()>, rank()>,
dense_rank()>, percent_rank()>, and
cume_dist()>
(Atri Sharma, Andrew Gierth)
Support VARIADIC>
aggregate functions (Tom Lane)
Allow polymorphic aggregates to have non-polymorphic state data
types (Tom Lane)
This allows proper declaration in SQL of aggregates like the built-in
aggregate array_agg()>.
Server-Side Languages
Add event trigger support to PL/Perl>
and PL/Tcl> (Dimitri Fontaine)
Convert numeric>
values to decimal> in PL/Python
(Szymon Guz, Ronan Dunklau)
Previously such values were converted to Python float> values,
risking loss of precision.
PL/pgSQL Server-Side Language
Add ability to retrieve the current PL/PgSQL call stack
using GET
DIAGNOSTICS>
(Pavel Stehule, Stephen Frost)
Add option
print_strict_params>
to display the parameters passed to a query that violated a
STRICT> constraint (Marko Tiikkaja)
Add variables plpgsql.extra_warnings>
and plpgsql.extra_errors> to enable additional PL/pgSQL
warnings and errors (Marko Tiikkaja, Petr Jelinek)
Currently only warnings/errors about shadowed variables are available.
libpq>
Make libpq's PQconndefaults()>
function ignore invalid service files (Steve Singer, Bruce Momjian)
Previously it returned NULL if an incorrect service file was
encountered.
Accept TLS> protocol versions beyond TLSv1>
in libpq (Marko Kreen)
Client Applications
Add option
-g>
to specify role membership (Chistopher Browne)
Add
option
--analyze-in-stages> to analyze in stages of
increasing granularity (Peter Eisentraut)
This allows minimal statistics to be created quickly.
Make with option
-n>
output current and potentially changed values (Rajeev Rastogi)
Make throw error for incorrect locale
settings, rather than silently falling back to a default choice
(Tom Lane)
Make return exit code 4> for
an inaccessible data directory (Amit Kapila, Bruce Momjian)
This behavior more closely matches the Linux Standard Base
(LSB>) Core Specification.
On Windows, ensure that a non-absolute
-D> path
specification is interpreted relative
to 's current directory
(Kumar Rajeev Rastogi)
Previously it would be interpreted relative to whichever directory
the underlying Windows service was started in.
Allow sizeof()> in ECPG
C array definitions (Michael Meskes)
Make ECPG properly handle nesting
of C-style comments in both C and SQL> text
(Michael Meskes)
Suppress No rows output in psql>
expanded>
mode when the footer is disabled (Bruce Momjian)
Allow Control-C to abort psql> when it's hung at
connection startup (Peter Eisentraut)
Backslash Commands
Make psql>'s \db+> show tablespace options
(Magnus Hagander)
Make \do+> display the functions
that implement the operators (Marko Tiikkaja)
Make \d+> output an
OID> line only if an oid column
exists in the table (Bruce Momjian)
Previously, the presence or absence of an oid
column was always reported.
Make \d> show disabled system triggers (Bruce
Momjian)
Previously, if you disabled all triggers, only user triggers
would show as disabled.
Fix \copy> to no longer require
a space between stdin> and a semicolon (Etsuro Fujita)
Output the row count at the end of \copy>, just
like COPY> already did (Kumar Rajeev Rastogi)
Fix \conninfo> to display the
server's IP> address for connections using
hostaddr> (Fujii Masao)
Previously \conninfo> could not display the server's
IP> address in such cases.
Show the SSL> protocol version in
\conninfo> (Marko Kreen)
Add tab completion for \pset>
(Pavel Stehule)
Allow \pset> with no arguments
to show all settings (Gilles Darold)
Make \s> display the name of the history file it wrote
without converting it to an absolute path (Tom Lane)
The code previously attempted to convert a relative file name to
an absolute path for display, but frequently got it wrong.
Allow options
-I>,
-P>,
-T> and
-n>
to be specified multiple times (Heikki Linnakangas)
This allows multiple objects to be restored in one operation.
Optionally add IF EXISTS> clauses to the DROP>
commands emitted when removing old objects during a restore (Pavel
Stehule)
This change prevents unnecessary errors when removing old objects.
The new
--if-exists> option
for , ,
and is only available
when
--clean> is also specified.
Add pg_basebackup> option
--xlogdir>
to specify the pg_xlog> directory location (Haribabu
Kommi)
Allow pg_basebackup> to relocate tablespaces in
the backup copy (Steeve Lennmark)
This is particularly useful for using pg_basebackup>
on the same machine as the primary.
Allow network-stream base backups to be throttled (Antonin Houska)
This can be controlled with the pg_basebackup>
--max-rate> parameter.
Source Code
Improve the way tuples are frozen to preserve forensic information
(Robert Haas, Andres Freund)
This change removes the main objection to freezing tuples as soon
as possible. Code that inspects tuple flag bits will need to be
modified.
No longer require function prototypes for functions marked with the
PG_FUNCTION_INFO_V1>
macro (Peter Eisentraut)
This change eliminates the need to write boilerplate prototypes.
Note that the PG_FUNCTION_INFO_V1> macro must appear
before the corresponding function definition to avoid compiler
warnings.
Remove SnapshotNow> and
HeapTupleSatisfiesNow()> (Robert Haas)
All existing uses have been switched to more appropriate snapshot
types. Catalog scans now use MVCC> snapshots.
Add an API> to allow memory allocations over one gigabyte
(Noah Misch)
Add psprintf()> to simplify memory allocation during
string composition (Peter Eisentraut, Tom Lane)
Support printf()> size modifier z> to
print size_t> values (Andres Freund)
Change API> of appendStringInfoVA()>
to better use vsnprintf()> (David Rowley, Tom Lane)
Allow new types of external toast datums to be created (Andres
Freund)
Add single-reader, single-writer, lightweight shared message queue
(Robert Haas)
Improve spinlock speed on x86_64 CPU>s (Heikki
Linnakangas)
Remove spinlock support for unsupported platforms
SINIX>, Sun3>, and
NS32K> (Robert Haas)
Remove IRIX> port (Robert Haas)
Reduce the number of semaphores required by
--disable-spinlocks> builds (Robert Haas)
Rewrite duplicate_oids> Unix shell script in
Perl> (Andrew Dunstan)
Add Test Anything Protocol (TAP>) tests for client
programs (Peter Eisentraut)
Currently, these tests are run by make check-world>
only if the
--enable-tap-tests> option was given
to configure>.
This might become the default behavior in some future release.
Add make targets
check-tests> and
installcheck-tests>, which allow selection of individual
tests to be run (Andrew Dunstan)
The default build rules now include all the formerly-optional tests.
Improve support for VPATH> builds of PGXS>
modules (Cédric Villemain, Andrew Dunstan, Peter Eisentraut)
Upgrade to Autoconf 2.69 (Peter Eisentraut)
Add a configure> flag that appends custom text to the
PG_VERSION> string (Oskari Saarenmaa)
This is useful for packagers building custom binaries.
Improve DocBook XML> validity (Peter Eisentraut)
Fix various minor security and sanity issues reported by the
Coverity> scanner (Stephen Frost)
Improve detection of invalid memory usage when testing
PostgreSQL> with Valgrind>
(Noah Misch)
Improve sample Emacs> configuration file
emacs.samples> (Peter Eisentraut)
Also add .dir-locals.el> to the top of the source tree.
Allow pgindent> to accept a command-line list
of typedefs (Bruce Momjian)
Make pgindent> smarter about blank lines
around preprocessor conditionals (Bruce Momjian)
Avoid most uses of dlltool
in Cygwin> and
Mingw> builds (Marco Atzeri, Hiroshi Inoue)
Support client-only installs in MSVC> (Windows) builds
(MauMau)
Additional Modules
Add extension to preload relation data
into the shared buffer cache at server start (Robert Haas)
This allows reaching full operating performance more quickly.
Add UUID> random number generator
gen_random_uuid()> to
(Oskari Saarenmaa)
This allows creation of version 4 UUID>s without
requiring installation of .
Allow to work with
the BSD> or e2fsprogs> UUID libraries,
not only the OSSP> UUID library (Matteo Beccati)
This improves the uuid-ossp> module's portability
since it no longer has to have the increasingly-obsolete OSSP
library. The module's name is now rather a misnomer, but we won't
change it.
Add option to to include trigger
execution time (Horiguchi Kyotaro)
Fix to not report rows from
uncommitted transactions as dead (Robert Haas)
Make functions
use regclass-type arguments (Satoshi Nagayasu)
While text-type arguments are still supported, they
may be removed in a future major release.
Improve consistency of output to honor
snapshot rules more consistently (Robert Haas)
Improve 's choice of trigrams for indexed
regular expression searches (Alexander Korotkov)
This change discourages use of trigrams containing whitespace, which
are usually less selective.
Allow to report a live log stream
with
--follow> (Heikki Linnakangas)
Store data more compactly (Stas Kelvich)
Existing data must be dumped/restored to use the new format.
The old format can still be read.
Reduce client-side memory usage by using
a cursor (Andrew Dunstan)
Dramatically reduce memory consumption
in (Bruce Momjian)
Pass 's user name (
-U>) option to
generated analyze scripts (Bruce Momjian)
Remove line length limit for pgbench> scripts (Sawada
Masahiko)
The previous line limit was BUFSIZ>.
Add long option names to pgbench> (Fabien Coelho)
Add pgbench> option
--rate> to control
the transaction rate (Fabien Coelho)
Add pgbench> option
--progress> to
print periodic progress reports
(Fabien Coelho)
Make pg_stat_statements> use a file, rather than
shared memory, for query text storage (Peter Geoghegan)
This removes the previous limitation on query text length, and
allows a higher number of unique statements to be tracked by default.
Allow reporting of pg_stat_statements>'s internal
query hash identifier (Daniel Farina, Sameer Thakur, Peter
Geoghegan)
Add the ability to retrieve all pg_stat_statements>
information except the query text (Peter Geoghegan)
This allows monitoring tools to fetch query text only for
just-created entries, improving performance during repeated querying
of the statistics.
Make pg_stat_statements> ignore DEALLOCATE>
commands (Fabien Coelho)
It already ignored PREPARE>, as well as planning time in
general, so this seems more consistent.
Save the statistics file into $PGDATA/pg_stat> at server
shutdown, rather than $PGDATA/global> (Fujii Masao)