Implementing a new Join Algorithm

Hi,
I am trying to test a new join algorithm by
implementing it on Postgresql.
It would be great if you could give me some start off
pointers so as to where all in the source code I will
have to make changes. (I figure that I need to make
executor nodes, so i might need to write nodeNewjoin.c
etc in src/backend/executor, and somehow get the
planner/optimizer to select the new algorithm)

I tried going through the developers guide (7.3.1) but
it has many figures missing, making my job of
understanding the mechanism very tough. The figures
I am referring to are
{PostgreSQL 7.3.1 Documentation
section 2.3.1: Figure \ref{parsetree},
\ref{where_clause}
section 2.3.2 Figure \ref{transformed},
\ref{transformed_where}
2.5.2 \ref{plan} \ref{simple_select}.
}
Could you please point out where these figures are
available.
Regards
Anagh Lal.

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