pg_dot is a script that reverse engineers the database diagram from
    PostgreSQL system tables. It tries to generate a diagram as similar as
    possible to the intended Entity-Relationship Model used, including
    generalizations/specializations, unnormalized attributes and other
    abstractions that are hidden inside the database.

    This script is similar to the famous postgresql_autodoc script, but
    generates output only for graphviz. Also unlike postgresql_autodoc,
    pg_dot handles table hierarchy and will soon support unnormalized
    attributes, weak relationships, schemas and anything else I can
    implement.

    How to use:
        1 - Make sure the environment variables that PostgreSQL uses are
            defined and pointing to the correct server and database. The
            variables are PGHOST, PGPORT, PGUSER and PGDATABASE;
        2 - Make sure you have read access to the database. If it uses a
            password authentication, then set up a ~/.pgpass file adequately;
        3 - Execute the pg_dot script and it should result in a png file
            that describes the database diagram. The name of the file will be
            the name of the database consulted.

                                                 Arthur Nascimento

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    pg_dot: database diagram reverse engineered from PostgreSQL system tables
    Copyright (C) 2011 Arthur Nascimento <[email protected]>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>
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