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<sect1 id="release-9-0">

<title>Release 9.0</title>

<listitem>

<para>

Easier database object permissions management. <link

linkend="SQL-GRANT"><command>GRANT</>/<command>REVOKE IN

SCHEMA</></link> supports mass permissions changes on existing objects,

while <link linkend="SQL-ALTERDEFAULTPRIVILEGES"><command>ALTER DEFAULT

PRIVILEGES</></link>allows control ofprivileges for objects created in

the future. Largeobjects (BLOBs) now support privilege management as

well.

linkend="SQL-GRANT"><command>GRANT</>/<command>REVOKE

INSCHEMA</></link> supports mass permissions changes, and

the <link linkend="SQL-ALTERDEFAULTPRIVILEGES"><command>ALTER

DEFAULTPRIVILEGES</></link>command controlsprivileges

of all newly-createdobjects. Large object permissions now

support <command>GRANT</>/<command>REVOKE</> aswell.

</para>

</listitem>

<listitem>

<para>

Broadly enhanced stored procedure support.

The <link linkend="SQL-DO"><command>DO</></link> statement permits

execution of <quote>anonymous</> code blocks, without having to

define a function first. Functions can now be called using named

parameters. PL/pgSQL is now installed by default, and PL/Perl and

PL/Python have been enhanced in several ways, including support for

Python3.

Add support for compiling on <link

linkend="install-win32-full">64-bit

<productname>Windows</></link> and running in 64-bit

mode.

</para>

</listitem>

<listitem>

<para>

Full support for <link linkend="install-win32">64-bit

<productname>Windows</></link>.

Broadly enhanced stored procedure support.

The <link linkend="SQL-DO"><command>DO</></link> statement permits

ad-hoc or anonymous code blocks. Functions can now be called using named

parameters. <link linkend="plpgsql">PL/pgSQL</link> is now installed by default,

and <link linkend="plperl">PL/Perl</link> and <link linkend="plpython">PL/Python</link>

have been enhanced in several ways, including support for Python3.

</para>

</listitem>

<listitem>

<para>

More advanced reporting queries, including additional windowing options

(<literal>PRECEDING</> and <literal>FOLLOWING</>) and the ability to

control the order in which values are fed to aggregate functions.

More advanced reporting queries with additional <link

linkend="functions-window">window functions</link>

(<literal>PRECEDING</> and <literal>FOLLOWING</>) and the ability

to <link linkend="syntax-aggregates"><literal>ORDER BY</></link>

inside aggregate functions.

</para>

</listitem>

<listitem>

<para>

New triggerfeatures, including

SQL-standard-compliant <link

linkend="SQL-CREATETRIGGER">per-column triggers</link> and

Triggers now support two newfeatures,

SQL-compliant <link

linkend="SQL-CREATETRIGGER">per-column triggers</link>, and

conditional trigger execution.

</para>

</listitem>

<listitem>

<para>

<link linkend="ddl-constraints-exclusion">Exclusion constraints</link>.

enforcement of complex conditions.

New and enhanced security features, including<link linkend="client-authentication">RADIUS authentication</link>,

for testing password strength.

</para>

</listitem>

<listitem>

<para>

New and enhanced security features, including RADIUS authentication,

LDAP authentication improvements, and a new contrib module

<link linkend="passwordcheck"><filename>passwordcheck</></link>

for testing password strength.

The <link linkend="SQL-LISTEN"><command>LISTEN</></link>/<link

linkend="SQL-NOTIFY"><command>NOTIFY</></link>

feature has been overhauled to make it into

a high-performance event queuing system. It now stores

events in a memory-based queue, and it now allows delivery

of a string payload to listeners with each event.

</para>

</listitem>

<listitem>

<para>

New high-performance implementation of the

<link linkend="SQL-LISTEN"><command>LISTEN</></link>/<link

linkend="SQL-NOTIFY"><command>NOTIFY</></link> feature.

Pending events are now stored in a memory-based queue rather than

a table. Also, a <quote>payload</> string can be sent with each

event, rather than transmitting just an event name as before.

Add <link linkend="pgupgrade"><filename>/contrib/pg_upgrade</></link>

to support in-place upgrades from 8.3 or 8.4 to 9.0.

</para>

</listitem>

<listitem>

<para>

New implementation of

<link linkend="SQL-VACUUM"><command>VACUUM FULL</></link>.

This command now rewrites the entire table and indexes, rather than

moving individual rows to compact space. It is substantially faster

in most cases, and no longer results in index bloat.

Multiple performance enhancements for specific types of queries,

including join elimination, which optimizes automatically generated

queries, such as those produced by object-relational mappers (ORMs).

</para>

</listitem>

<listitem>

<para>

New contrib module

<link linkend="pgupgrade"><filename>pg_upgrade</></link>

to support in-place upgrades from 8.3 or 8.4 to 9.0.

<link linkend="ddl-constraints-exclusion">Exclusion constraints</link>

let database designers define uniqueness based on complex

criteria, including for non-scalar data such as time periods,

ranges and arrays.

</para>

</listitem>

<listitem>

<para>

Multiple performance enhancements for specific typesofqueries,

object-relational mappers (ORMs).

As part of our decade-long effort to eliminate the painofVACUUM,

indexes, rather than moving around single rows to compact space.

</para>

</listitem>

<listitem>

<para>

<link linkend="SQL-EXPLAIN"><command>EXPLAIN</></link> enhancements.

The output isnow available in JSON, XML, or YAML format, andincludes

<link linkend="using-explain"><command>EXPLAIN</command></link>

plans arenow available in JSON, XML and YAML format, andinclude

buffer utilization and other data not previously available.

</para>

</listitem>

<listitem>

<para>

<link linkend="hstore"><filename>hstore</></link>improvements,

including new functions and greater data capacity.

The<link linkend="hstore">HStore optional module</link>has been improved with new functions and greater

data capacity to make it a high-performance key-value store.

</para>

</listitem>

<listitem>

<para>

Allow aggregate functions to use <literal>ORDER BY</> (Andrew

Allow aggregate functions to use <link

linkend="syntax-aggregates"><literal>ORDER BY</></> (Andrew

Gierth)

</para>