E.48. Release 11.2
Release date: 2019-02-14
This release contains a variety of fixes from 11.1. For information about new features in major release 11, seeSection E.50.
E.48.1. Migration to Version 11.2
A dump/restore is not required for those running 11.X.
However, if you are upgrading from a version earlier than 11.1, seeSection E.49.
E.48.2. Changes
By default, panic instead of retrying after
fsync()
failure, to avoid possible data corruption (Craig Ringer, Thomas Munro)Some popular operating systems discard kernel data buffers when unable to write them out, reporting this as
fsync()
failure. If we reissue thefsync()
request it will succeed, but in fact the data has been lost, so continuing risks database corruption. By raising a panic condition instead, we can replay from WAL, which may contain the only remaining copy of the data in such a situation. While this is surely ugly and inefficient, there are few alternatives, and fortunately the case happens very rarely.A new server parameterdata_sync_retry has been added to control this; if you are certain that your kernel does not discard dirty data buffers in such scenarios, you can set
data_sync_retry
toon
to restore the old behavior.Include each major release branch's release notes in the documentation for only that branch, rather than that branch and all later ones (Tom Lane)
The duplication induced by the previous policy was getting out of hand. Our plan is to provide a full archive of release notes on the project's web site, but not duplicate it within each release.
Fix handling of unique indexes with
INCLUDE
columns on partitioned tables (Álvaro Herrera)The uniqueness condition was not checked properly in such cases.
Ensure that
NOT NULL
constraints of a partitioned table are honored within its partitions (Álvaro Herrera, Amit Langote)Update catalog state correctly for partition table constraints when detaching their partition (Amit Langote, Álvaro Herrera)
Previously, the
pg_constraint
.conislocal
field for such a constraint might improperly be left asfalse
, rendering it undroppable. A dump/restore or pg_upgrade would cure the problem, but if necessary, the catalog field can be adjusted manually.Create or delete foreign key enforcement triggers correctly when attaching or detaching a partition in a partitioned table that has a foreign-key constraint (Amit Langote, Álvaro Herrera)
Avoid useless creation of duplicate foreign key constraints in partitioned tables (Álvaro Herrera)
When an index is created on a partitioned table using
ONLY
, and there are no partitions yet, mark it valid immediately (Álvaro Herrera)Otherwise there is no way to make it become valid.
Use a safe table lock level when detaching a partition (Álvaro Herrera)
The previous locking level was too weak and might allow concurrent DDL on the table, with bad results.
Fix problems with applying
ON COMMIT DROP
andON COMMIT DELETE ROWS
to partitioned tables and tables with inheritance children (Michael Paquier)Disallow
COPY FREEZE
on partitioned tables (David Rowley)This should eventually be made to work, but it may require a patch that's too complicated to risk back-patching.
Fix possible index corruption when the indexed column has a“fast default” (that is, it was added by
ALTER TABLE ADD COLUMN
with a constant non-NULL default value specified, after the table already contained some rows) (Andres Freund)Correctly adjust“fast default” values during
ALTER TABLE ... ALTER COLUMN TYPE
(Andrew Dunstan)Avoid possible deadlock when acquiring multiple buffer locks (Nishant Fnu)
Avoid deadlock between GIN vacuuming and concurrent index insertions (Alexander Korotkov, Andrey Borodin, Peter Geoghegan)
This change partially reverts a performance improvement, introduced in version 10.0, that attempted to reduce the number of index pages locked during deletion of a GIN posting tree page. That's now been found to lead to deadlocks, so we've removed it pending closer analysis.
Avoid deadlock between hot-standby queries and replay of GIN index page deletion (Alexander Korotkov)
Fix possible crashes in logical replication when index expressions or predicates are in use (Peter Eisentraut)
Avoid useless and expensive logical decoding of TOAST data during a table rewrite (Tomas Vondra)
Fix logic for stopping a subset of WAL senders when synchronous replication is enabled (Paul Guo, Michael Paquier)
Avoid possibly writing an incorrect replica identity field in a tuple deletion WAL record (Stas Kelvich)
Prevent incorrect use of WAL-skipping optimization during
COPY
to a view or foreign table (Amit Langote, Michael Paquier)Make the archiver prioritize WAL history files over WAL data files while choosing which file to archive next (David Steele)
Fix possible crash in
UPDATE
with a multipleSET
clause using a sub-SELECT
as source (Tom Lane)Fix crash when zero rows are fed to
json[b]_populate_recordset()
orjson[b]_to_recordset()
(Tom Lane)Avoid crash iflibxml2 returns a null error message (Sergio Conde Gómez)
Fix incorrect JIT tuple deforming code for tables with many columns (more than approximately 800) (Andres Freund)
Fix performance and memory leakage issues in hash-based grouping (Andres Freund)
Fix spurious grouping-related parser errors caused by inconsistent handling of collation assignment (Andrew Gierth)
In some cases, expressions that should be considered to match were not seen as matching, if they included operations on collatable data types.
Fix parsing of collation-sensitive expressions in the arguments of a
CALL
statement (Peter Eisentraut)Ensure proper cleanup after detecting an error in the argument list of a
CALL
statement (Tom Lane)Check whether the comparison function underlying
LEAST()
orGREATEST()
is leakproof, rather than just assuming it is (Tom Lane)Actual information leaks from btree comparison functions are typically hard to provoke, but in principle they could happen.
Fix incorrect planning of queries involving nested loops both above and below a Gather plan node (Tom Lane)
If both levels of nestloop needed to pass the same variable into their right-hand sides, an incorrect plan would be generated.
Fix incorrect planning of queries in which a lateral reference must be evaluated at a foreign table scan (Tom Lane)
Fix planner failure when the first column of a row comparison matches an index column, but later column(s) do not, and the index has included (non-key) columns (Tom Lane)
Fix corner-case underestimation of the cost of a merge join (Tom Lane)
The planner could prefer a merge join when the outer key range is much smaller than the inner key range, even if there are so many duplicate keys on the inner side that this is a poor choice.
Avoid O(N^2) planning time growth when a query contains many thousand indexable clauses (Tom Lane)
Improve planning speed for large inheritance or partitioning table groups (Amit Langote, Etsuro Fujita)
Improve
ANALYZE
's handling of concurrently-updated rows (Jeff Janes, Tom Lane)Previously, rows deleted by an in-progress transaction were omitted from
ANALYZE
's sample, but this has been found to lead to more inconsistency than including them would do. In effect, the sample now corresponds to an MVCC snapshot as ofANALYZE
's start time.Make
TRUNCATE
ignore inheritance child tables that are temporary tables of other sessions (Amit Langote, Michael Paquier)This brings
TRUNCATE
into line with the behavior of other commands. Previously, such cases usually ended in failure.Fix
TRUNCATE
to update the statistics counters for the right table (Tom Lane)If the truncated table had a TOAST table, that table's counters were reset instead.
Process
ALTER TABLE ONLY ADD COLUMN IF NOT EXISTS
correctly (Greg Stark)Allow
UNLISTEN
in hot-standby mode (Shay Rojansky)This is necessarily a no-op, because
LISTEN
isn't allowed in hot-standby mode; but allowing the dummy operation simplifies session-state-reset logic in clients.Fix missing role dependencies in some schema and data type permissions lists (Tom Lane)
In some cases it was possible to drop a role to which permissions had been granted. This caused no immediate problem, but a subsequent dump/reload or upgrade would fail, with symptoms involving attempts to grant privileges to all-numeric role names.
Prevent use of a session's temporary schema within a two-phase transaction (Michael Paquier)
Accessing a temporary table within such a transaction has been forbidden for a long time, but it was still possible to cause problems with other operations on temporary objects.
Ensure relation caches are updated properly after adding or removing foreign key constraints (Álvaro Herrera)
This oversight could result in existing sessions failing to enforce a newly-created constraint, or continuing to enforce a dropped one.
Ensure relation caches are updated properly after renaming constraints (Amit Langote)
Fix replay of GiST index micro-vacuum operations so that concurrent hot-standby queries do not see inconsistent state (Alexander Korotkov)
Prevent empty GIN index pages from being reclaimed too quickly, causing failures of concurrent searches (Andrey Borodin, Alexander Korotkov)
Fix edge-case failures in float-to-integer coercions (Andrew Gierth, Tom Lane)
Values very slightly above the maximum valid integer value might not be rejected, and then would overflow, producing the minimum valid integer instead. Also, values that should round to the minimum or maximum integer value might be incorrectly rejected.
Fix parsing of space-separated lists of host names in the
ldapserver
parameter of LDAP authentication entries inpg_hba.conf
(Thomas Munro)When making a PAM authentication request, don't set the
PAM_RHOST
variable if the connection is via a Unix socket (Thomas Munro)Previously that variable would be set to
[local]
, which is at best unhelpful, since it's supposed to be a host name.Disallow setting
client_min_messages
higher thanERROR
(Jonah Harris, Tom Lane)Previously, it was possible to set this variable to
FATAL
orPANIC
, which had the effect of suppressing transmission of ordinary error messages to the client. However, that's contrary to guarantees that are given in thePostgreSQL wire protocol specification, and it caused some clients to become very confused. In released branches, fix this by silently treating such settings as meaningERROR
instead. Version 12 and later will reject those alternatives altogether.Fixecpglib to use
uselocale()
or_configthreadlocale()
in preference tosetlocale()
(Michael Meskes, Tom Lane)Since
setlocale()
is not thread-local, and might not even be thread-safe, the previous coding caused problems in multi-threadedecpg applications.