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<para>

Supportforthe SQL/XML standard, including new operators and

an<type>XML</type> data type

Support the SQL/XML standard, including new operators and an

<type>XML</type> data type

</para>

</listitem>

<listitem>

<para>

Universally Unique Identifier (<type>UUID</>) data type

AddUniversally Unique Identifier (<type>UUID</>) data type

</para>

</listitem>

<listitem>

<para>

Arrays of composite types

Support arrays of composite types

</para>

</listitem>

<listitem>

<para>

Control over whether <literal>NULL</>s sort first or last

Add control over whether <literal>NULL</>s sort first or last

</para>

</listitem>

<listitem>

<para>

Updatable cursors

Support updatable cursors

</para>

</listitem>

<listitem>

<para>

Multiple autovacuum worker processes, and other autovacuum improvements

Support multiple concurrent autovacuum processes, and other

autovacuum improvements

</para>

</listitem>

<listitem>

<para>

Thebackend database servercan now be compiled with

Allow thebackend database serverto be compiled with

<productname>Microsoft Visual C++</>

</para>

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<listitem>

<para>

Asynchronous commit allows transactions to be committed but on-disk

changes to be delayed

Asynchronous commit delays writes to WAL for committed transactions

</para>

</listitem>

<listitem>

<para>

Heap-Only Tuples (<acronym>HOT</>) accelerate<command>UPDATE</>

Heap-Only Tuples (<acronym>HOT</>) acceleratespace reuse for

</para>

</listitem>

<listitem>

<para>

Reduction of per-field and per-row storage requirements

Reduce per-field and per-row storage requirements

</para>

</listitem>

<listitem>

<para>

The array name for a base data type is no longerrequired to

be the datatype name with an underscore prefix

The array name for a base data type is no longeralways the data

type name with an underscore prefix

</para>

<para>

<listitem>

<para>

Commandsthat are disallowedin transaction blocks are now also

disallowed inmultiple-statement query strings (Tom)

Commandsrejectedin transaction blocks are now also rejected in

multiple-statement query strings (Tom)

</para>

<para>

<listitem>

<para>

More checks for invalidly-encoded data (Andrew)

Add more checks for invalidly-encoded data (Andrew)

</para>

<para>

<listitem>

<para>

Ensure that <function>chr()</function> cannot create invalidly

encoded values (Andrew)

Ensure that <function>chr()</function> cannot create

invalidly-encoded values (Andrew)

</para>

<para>

In UTF8-encoded databases the argument is processed as a Unicode

code point. In other multi-byte encodings the argument must

designate a 7-bit ASCII character, or an error is raised. Zero

also causes an error. <function>ascii()</function> has been

adjusted as well to match this behavior.

</para>

In UTF8-encoded databases the argument is now processed as a Unicode

code point. In other multi-byte encodings the argument must designate

a 7-bit ASCII character, or an error is raised. Zero also causes an

error. <function>ascii()</function> has been adjusted as well to

match this behavior.

</para>

</listitem>

<listitem>

The two argument form of <function>convert()</function> has been

removed. The three argument form now takes a <type>BYTEA</type>

first argument and returns a <type>BYTEA</type>. To cover this

loss three new functionsare introduced:

loss three new functionswere added:

</para>

<itemizedlist>

</para>

<para>

For example, <function>pg_database_size()</function> now

requires<literal>CONNECT</> permission, which is granted to

everyone bydefault. <function>pg_tablespace_size()</function>

requires<literal>CREATE</> permission in the tablespace, orthe

tablespace is the default tablespace for the database.

For example, <function>pg_database_size()</function> now requires

<literal>CONNECT</> permission, which is granted to everyone by

default. <function>pg_tablespace_size()</function> requires

<literal>CREATE</> permission in the tablespace, oris allowed if

thetablespace is the default tablespace for the database.

</para>

</listitem>

<listitem>

<para>

New C macros for handling variable-length data values (Greg

Add C macros for handling variable-length data values (Greg

Stark, Tom)

</para>

<listitem>

<para>

Asynchronous commitallows transactions tobecommittedbut on-disk

changes to be delayed(Simon)

Asynchronous commitdelays writes toWAL forcommittedtransactions

(Simon)

</para>

<para>

This feature dramatically increases performance for data

modification queries. The disadvantage is that because on-disk

changes are delayed, if the operating system crashes before data

is written to the disk, committed data will be lost. This is

useful only for applications that can accept some data loss.

Unlike <varname>fsync</varname>, asynchronous commit does not

risk database corruption; the worst case is that after an

operating system crash the last few reportedly-committed

transactions will be missing.

This feature dramatically increases performance for data-modifying

queries. The disadvantage is that because on-disk changes are

delayed, if the operating system crashes before data is written to

the disk, committed data will be lost. This is useful only for

applications that can accept some data loss. Unlike

<varname>fsync</varname>, asynchronous commit does not risk database

corruption; the worst case is that after an operating system crash

the last few reportedly-committed transactions will be missing.

This feature is enabled turning <varname>synchronous_commit</>

<literal>off</> and setting <varname>wal_writer_delay</>.

</para>

</listitem>

<listitem>

<para>

Heap-Only Tuples (<acronym>HOT</>) accelerate<command>UPDATE</>

space reuse (Pavan Deolasee, with ideas from many others)

Heap-Only Tuples (<acronym>HOT</>) acceleratespace reuse for

<command>UPDATE</>s (Pavan Deolasee, with ideas from many others)

</para>

<para>

<listitem>

<para>

Reduction of per-field and per-row storage requirements (Greg

Stark)

Reduce per-field and per-row storage requirements (Greg Stark)

</para>

<para>

Unless WAL archiving is enabled, it is possible to just

<function>fsync()</> the table at the end of the command,

increasing performance. Additional WAL efficiencies were also

added.

made.

</para>

</listitem>

<para>

This is accomplished by starting the new sequential scan in the

middle of the table (where the other sequential scan is already

in-progress) and wrapping around to the beginning to finish.

Thismay affect the orderin which rowsare returnedin a

non-<literal>ORDER BY</>query.

in-progress) and wrapping around to the beginning to finish. This

may affect the orderof returned rows in a non-<literal>ORDER BY</>

query.

</para>

</listitem>

<listitem>

<para>

Add support for GSSAPI authentication (Henry Hotz, Magnus)

Support GSSAPI authentication (Henry Hotz, Magnus)

</para>

</listitem>

<listitem>

<para>

Arrange to put TOAST tables belonging to temporary tables into

special schemas named

Place temporary table TOAST tables in a special schemas named

<literal>pg_toast_temp_<replaceable>nnn</></literal> (Tom)

</para>

<listitem>

<para>

Text search capability is now in core Postgres (Teodor, Oleg)

Full text search now fully integrated into the core database

system (Teodor, Oleg)

</para>

<para>

<listitem>

<para>

Control over whether <literal>NULL</>s sort first or last (Teodor, Tom)

Add control over whether <literal>NULL</>s sort first or last (Teodor, Tom)

</para>

<para>

<listitem>

<para>

Updatable cursors using <literal>UPDATE/DELETE WHERE CURRENT

OF</> (Arul Shaji, Tom)

Support updatable cursors (Arul Shaji, Tom)

</para>

<para>

<listitem>

<para>

Allow <command>ALTER VIEW ... RENAME TO</command> and <command>ALTER

Add <command>ALTER VIEW ... RENAME TO</command> and <command>ALTER

SEQUENCE ... RENAME TO</command> (David Fetter, Neil)

</para>

<listitem>

<para>

Support for the SQL/XML standard, including new operators and an

<type>XML</type> data type (Nikolay Samokhvalov, Peter)

Support the SQL/XML standard, including new operators and an

<type>XML</type> data type (Nikolay Samokhvalov, Peter)

</para>

</listitem>

<listitem>

<para>

Universally Unique Identifier (<type>UUID</>) data type (Gevik

AddUniversally Unique Identifier (<type>UUID</>) data type (Gevik

Babakhani, Neil)

</para>

<listitem>

<para>

Thebackend database servercan now be compiled with

Allow thebackend database serverto be compiled with

<productname>Microsoft Visual C++</> (Magnus and others)

</para>

<listitem>

<para>

Native shared memory implementation for Windows (Magnus)

Add native shared memory implementation for Windows (Magnus)

</para>

</listitem>