Vertical Partitioning with TOAST

Hi all,

I wrote a experimental patch for a vertical partitioning
function.

I decided to use the code of TOAST to create the function
easily. In a word, the row that the user specified is forcedly
driven out with TOAST.

The performance gain of 10% was seen by driving out c_data of the
customer table in the DBT-2 benchmark in our environment.

The mechanism of TOAST is an overdesigned system to use it for a
vertical partitioning. Because the overhead of processing is large,
the performance might down according to the environment.

There are seriously a lot of things that should be considered if
a vertical partitioning is mounted.
For instance, TOAST index is omitted, and ctid is used for link.

Your comments are welcome. Thanks.

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How To Use
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Use "ALTER TABLE" command.
http://www.postgresql.org/docs/8.1/static/sql-altertable.html

ALTER TABLE name ALTER COLUMN column SET STRAGE FORCEEXTERNAL;

I do not understand whether "FORCEEXTERNAL" is an appropriate
word. Please teach when there is a better word...

--
Junji Teramoto