NAME

GraphViz::DBI - Graph database tables and relations

VERSION

version 1.100860

SYNOPSIS

  use GraphViz::DBI;
  my $dbh = DBI->connect('...', '...', '...');
  print GraphViz::DBI->new($dbh)->graph_tables->as_png;

DESCRIPTION

This module constructs a graph for a database showing tables and connecting them if they are related. While or after constructing the object, pass an open database handle, then call "graph_tables" to determine database metadata and construct a GraphViz graph from the table and field information.

The methods described here are defined by this class; all other method calls are passed to the underlying GraphViz object:

METHODS

new([$dbh])

Constructs the object; also creates a GraphViz object. The constructor accepts an optional open database handle.

set_dbh($dbh)

Sets the database handle.

get_dbh()

Returns the database handle.

get_tables()

Returns the tables defined in the database.

is_table($table)

Checks the database metadata whether the argument is a valid table name.

is_foreign_key($table, $field)

Determines whether the field belonging to the table is a foreign key into some other table. If so, it is expected to return the name of that table. If not, it is expected to return a false value.

For example, if there is a table called "product" and another table contains a field called "product_id", then to indicate that this field is a foreign key into the product table, the method returns "product". This is the logic implemented in this class. You can override this method in a subclass to suit your needs.

graph_tables()

This method goes through all tables and fields and calls appropriate methods to determine which tables and which dependencies exist, then hand the results over to GraphViz. It returns the GraphViz object.

FEATURE IDEAS

Test with various database drivers to see whether they support the metadata interface.
Make each table a vertical port with dependencies using those ports.
Provide the possibility to name edges to specify the type of relationship ('has-a', 'is-a', etc.).

INSTALLATION

See perlmodinstall for information and options on installing Perl modules.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests through the web interface at <http://rt.cpan.org/Public/Dist/Display.html?Name=GraphViz-DBI>.

AVAILABILITY

The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a CPAN site near you, or see <http://search.cpan.org/dist/GraphViz-DBI/>.

The development version lives at <http://github.com/hanekomu/GraphViz-DBI/>. Instead of sending patches, please fork this project using the standard git and github infrastructure.

AUTHOR

  Marcel Gruenauer <marcel@cpan.org>

COPYRIGHT AND LICENSE

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.