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

<literal>ORDER BY ... NULLS FIRST/LAST</>

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

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Updatable cursors using <literal>UPDATE/DELETE WHERE CURRENT OF</>

Updatable cursors

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<para>

Numerous improvements in logging and statistics collection,

including the ability to emit postmaster log messages in

<acronym>CSV</> format, which can be loaded into a database

table for analysis

Numerous improvements in logging and statistics collection

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<para>

Support Security Service Provider Interface (SSPI) on

authenticationfor Windows and GSSAPI

Support Security Service Provider Interface (<acronym>SSPI</>) for

authenticationon Windows

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<para>

Asynchronous commitoptionallows transactions to be committed

but on-diskchanges to be delayed

Asynchronous commit allows transactions to be committed but on-disk

changes to be delayed

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Asynchronous commitoptionallows transactions to be committed

but on-diskchanges to be delayed (Simon)

Asynchronous commit allows transactions to be committed but on-disk

changes to be delayed (Simon)

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<para>

To allow high concurrency <productname>PostgreSQL</>retains old

versions of updated rows. Previously only <command>VACUUM</>

could reuse space taken bydead rows. With <acronym>HOT</> dead

rowspace can be reused at the time of <command>UPDATE</> or

<command>INSERT</>. This allows for more consistent performance.

<acronym>HOT</> even allows deleted row space reuse.

<command>UPDATE</> space reuse isonly possible if no modified

columns are indexed.

To allow high concurrency <command>UPDATE</>creates a new tuple,

rather than replacing the old tuple. Previously only

<command>VACUUM</>could reuse space taken byold tuples. With

<acronym>HOT</> dead tuplespace can be reused at the time of

<command>UPDATE</> or <command>INSERT</>.This allows for more

consistent performance.<acronym>HOT</> even allows deleted row

space reuse. <acronym>HOT</> space reuse isnot possible if

<command>UPDATE</> changes indexed columns.

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This is done by scanning the table and using a filter to save

the few requested rows, rather than sorting the entire table.

This is done by sequentially scanning the table and using a filter

to save the few requested rows, rather than sorting the entire

table. This is used if there is no matching index.

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<para>

Support Security Service Provider Interface (SSPI)

authentication on Windows (Magnus)

Support Security Service Provider Interface (<acronym>SSPI</>) for

authentication on Windows

</para>

<para>

This also adds support for the <acryonym>GSSAPI</> authentication

<acronym>API</>.

</para>

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Allow logfile creation in CSV format (Arul Shaji, Greg Smith,

Andrew Dunstan)

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The CSV file can be loaded into a database table for analysis.

</para>

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<para>

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

<literal>ORDER BY ... NULLS FIRST/LAST</> (Teodor, Tom)

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

</para>

<para>

The syntax is <literal>ORDER BY ... NULLS FIRST/LAST</>.

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<para>

This eliminates the need to reference a primary key to update or

delete rows returned by a cursor.

This eliminates the need to reference a primary key to

<command>UPDATE</> or <command>DELETE</> rows returned by a cursor.

The syntax is <literal>UPDATE/DELETE WHERE CURRENT OF</>.

</para>

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