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<para>

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

most <command>UPDATE</>s

most <command>UPDATE</>s and <command>DELETE</>s

</para>

</listitem>

<listitem>

<para>

Heap-Only Tuples (<acronym>HOT</>) accelerate space reuse for most

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

<command>UPDATE</>s and <command>DELETE</>s (Pavan Deolasee, with

ideas from many others)

</para>

<para>

<command>UPDATE</>s and <command>DELETE</>s leave dead tuples

behind, as do failed <command>INSERT</>s. Previously only

<command>VACUUM</> could reclaim space taken by dead tuples. With

<acronym>HOT</> dead tuple space can be reclaimed at the time of

<command>UPDATE</> or <command>INSERT</> if no changes are made to

<command>INSERT</> or <command>UPDATE</> if no changes are made to

indexed columns. This allows for more consistent performance.

Also, <acronym>HOT</> avoids adding duplicate index entries.

</para>