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<chapter id="high-availability">

<title>High Availability and Load Balancing</title>

</para>

<para>

<productname>PostgreSQL</> does not offer this type ofload

balancing,though <productname>PostgreSQL</> two-phase commit

(<xreflinkend="sql-prepare-transaction"

<productname>PostgreSQL</> does not offer this type ofreplication,

though <productname>PostgreSQL</> two-phase commit (<xref

linkend="sql-prepare-transaction"

endterm="sql-prepare-transaction-title"> and <xref

linkend="sql-commit-prepared" endterm="sql-commit-prepared-title">)

can be used to implement this in application code or middleware.

<listitem>

<para>

This allows multiple servers to work concurrently on a single

Many of the above solutions allow multiple servers handle multiple sessions, but none allow a single query to use

multiple server to complete fas to This allows multiple servers to work concurrently on a single

query. One possible way this could work is for the data to be

split among servers and for each server to execute its part of

the query and results sent to a central server to be combined