<note>

<title>Release Date</title>

<simpara>2016-??-??</simpara>

<simpara>Current as of 2016-05-08 (commit6f69b9639)</simpara>

<simpara>Current as of 2016-06-18 (commit100340e2d)</simpara>

</note>

<sect2>

2016-04-05 [11c8669c0] Add parallel query support functions for assorted aggreg

2016-04-08 [25fe8b5f1] Add a 'parallel_degree' reloption.

2016-04-27 [59eb55127] Fix EXPLAIN VERBOSE output for parallel aggregate.

2016-06-09 [c9ce4a1c6] Eliminate "parallel degree" terminology.

2016-06-16 [75be66464] Invent min_parallel_relation_size GUC to replace a hard-

-->

<para>

Parallel queries (Robert Haas, Amit Kapila, David Rowley, many others)

configuration parameters

<xref linkend="guc-max-parallel-workers-per-gather">,

<xref linkend="guc-force-parallel-mode">,

<xref linkend="guc-parallel-setup-cost">, and

<xref linkend="guc-parallel-tuple-cost">.

<xref linkend="guc-parallel-setup-cost">,

<xref linkend="guc-parallel-tuple-cost">, and

<xref linkend="guc-min-parallel-relation-size">.

</para>

</listitem>

2016-03-08 [77a1d1e79] Department of second thoughts: remove PD_ALL_FROZEN.

2016-03-10 [fd31cd265] Don't vacuum all-frozen pages.

2016-03-11 [7087166a8] pg_upgrade: Convert old visibility map format to new for

2016-06-17 [ede62e56f] Add VACUUM (DISABLE_PAGE_SKIPPING) for emergencies.

-->

<para>

Avoid re-vacuuming pages containing only frozen tuples

transaction wraparound prevention. This should greatly reduce the

cost of maintaining large tables containing mostly-unchanging data.

</para>

<para>

If necessary, vacuum can be forced to process all-frozen pages

using its new <literal>DISABLE_PAGE_SKIPPING</> option. This

should never be needed normally, but it might help for example

in recovering from visibility-map corruption.

</para>

</listitem>

<listitem>

2016-04-26 [72a98a639] Don't open formally non-existent segments in _mdfd_getse

2016-05-04 [a71248708] Fix transient mdsync() errors of truncated relations due

2016-02-16 [7975c5e0a] Allow the WAL writer to flush WAL at a reduced rate.

2016-06-10 [4bc0f165c] Change default of backend_flush_after GUC to 0 (disabled

-->

<para>

Where feasible, trigger kernel writeback after a configurable number

<listitem>

<!--

2016-04-08 [137805f89] Use Foreign Key relationships to infer multi-column join

2016-06-07 [77ba61080] Revert "Use Foreign Key relationships to infer multi-col

2016-06-18 [100340e2d] Restore foreign-key-aware estimation of join relation si

-->

<para>

Use foreign key relationships to infer selectivity for multi-column

Use foreign key relationships to infer selectivity for

join predicates (Tomas Vondra, David Rowley)

</para>

<para>

If a table <literal>t</> has amulti-columnforeign key restriction,

If a table <literal>t</> has a foreign key restriction,

say <literal>(a,b) REFERENCES r (x,y)</>, then a <literal>WHERE</>

condition such as <literal>t.a = r.x AND t.b = r.y</> cannot select

more than one <literal>r</> row per <literal>t</> row. The planner

<listitem>

<!--

2016-04-08 [5c3c3cd0a] Enhanced custom error in PLPythonu

2016-06-11 [020140d84] PL/Python: Rename new keyword arguments of plpy.error()

-->

<para>

Extend PL/Python's error-reporting and message-reporting functions to

<listitem>

<!--

2016-03-21 [dea2b5960] Improve header output from psql's \watch command.

2016-06-15 [9901d8ac2] Use strftime("%c") to format timestamps in psql's \watch

-->

<para>

Improve the headers output by the <command>\watch</> command

Include the <command>\pset title</> string if one has been set, and

shorten the prefabricated part of the header to be

<literal><replaceable>timestamp</> (every <replaceable>N</>s)</literal>.

Also, the timestamp format now obeys <application>psql</>'s locale

environment.

</para>

</listitem>

<listitem>

<!--

2016-04-21 [f039eaac7] Allow queries submitted by postgres_fdw to be canceled.

2016-05-16 [1b812afb0] Fix multiple problems in postgres_fdw query cancellation

-->

<para>

Transmit query cancellation requests to the remote server