postgresql/contrib/oracle/ora2pg.html

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<TITLE>Ora2Pg - Oracle to PostgreSQL database schema converter</TITLE>
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<!-- INDEX BEGIN -->
<UL>
<LI><A HREF="#NAME">NAME</A>
<LI><A HREF="#SYNOPSIS">SYNOPSIS</A>
<LI><A HREF="#DESCRIPTION">DESCRIPTION</A>
<LI><A HREF="#ABSTRACT">ABSTRACT</A>
<LI><A HREF="#REQUIREMENT">REQUIREMENT</A>
<LI><A HREF="#PUBLIC_METHODS">PUBLIC METHODS</A>
<UL>
<LI><A HREF="#new_HASH_OPTIONS">new HASH_OPTIONS</A>
<LI><A HREF="#export_sql_FILENAME">export_sql FILENAME</A>
</UL>
<LI><A HREF="#PUBLIC_METHODS">PUBLIC METHODS</A>
<UL>
<LI><A HREF="#_init_HASH_OPTIONS">_init HASH_OPTIONS</A>
<LI><A HREF="#_tables">_tables</A>
<LI><A HREF="#_get_sql_data">_get_sql_data</A>
<LI><A HREF="#_sql_type_INTERNAL_TYPE_LENGTH">_sql_type INTERNAL_TYPE LENGTH</A>
<LI><A HREF="#_column_info_TABLE">_column_info TABLE</A>
<LI><A HREF="#_primary_key_TABLE">_primary_key TABLE</A>
<LI><A HREF="#_unique_key_TABLE">_unique_key TABLE</A>
<LI><A HREF="#_foreign_key_TABLE">_foreign_key TABLE</A>
<LI><A HREF="#_get_privilege">_get_privilege </A>
</UL>
<LI><A HREF="#AUTHOR">AUTHOR</A>
<LI><A HREF="#COPYRIGHT">COPYRIGHT</A>
<LI><A HREF="#BUGS">BUGS</A>
<LI><A HREF="#SEE_ALSO">SEE ALSO</A>
</UL>
<!-- INDEX END -->
<HR>
<P>
<H1><A NAME="NAME">NAME</A></H1>
<P>
Ora2Pg - Oracle to PostgreSQL database schema converter
<P>
<HR>
<H1><A NAME="SYNOPSIS">SYNOPSIS</A></H1>
<P>
<PRE> BEGIN {
$ENV{ORACLE_HOME} = '/usr/local/oracle/oracle816';
}
</PRE>
<P>
<PRE> use strict;
</PRE>
<P>
<PRE> use Ora2Pg;
</PRE>
<P>
<PRE> # Init the database connection
my $dbsrc = 'dbi:Oracle:host=testdb.samse.fr;sid=TEST;port=1521';
my $dbuser = 'system';
my $dbpwd = 'manager';
</PRE>
<P>
<PRE> # Create an instance of the Ora2Pg perl module
my $schema = new Ora2Pg (
datasource =&gt; $dbsrc, # Database DBD datasource
user =&gt; $dbuser, # Database user
password =&gt; $dbpwd, # Database password
);
</PRE>
<P>
<PRE> # Create the POSTGRESQL representation of all objects in the database
$schema-&gt;export_schema(&quot;output.sql&quot;);
</PRE>
<P>
<PRE> exit(0);
</PRE>
<P>
<HR>
<H1><A NAME="DESCRIPTION">DESCRIPTION</A></H1>
<P>
Ora2Pg is a perl OO module used to export an Oracle database schema to a
PostgreSQL compatible schema.
<P>
It simply connect to your Oracle database, extract its structure and
generate a SQL script that you can load into your PostgreSQL database.
<P>
I'm not a Oracle DBA so I don't really know something about its internal
structure so you may find some incorrect things. Please tell me what is
wrong and what can be better.
<P>
It currently only dump the database schema, with primary, unique and
foreign keys. I've tried to excluded internal system tables but perhaps not
enougt, please let me know.
<P>
<HR>
<H1><A NAME="ABSTRACT">ABSTRACT</A></H1>
<P>
The goal of the Ora2Pg perl module is to cover all part needed to export an
Oracle database to a PostgreSQL database without other thing that provide
the connection parameters to the Oracle database.
<P>
Features must include:
<P>
<PRE> - database schema export (done)
- grant export (done)
- predefined function/trigger export (todo)
- data export (todo)
- sql query converter (todo)
</PRE>
<P>
My knowledge regarding database is really poor especially for Oracle so
contribution is welcome.
<P>
<HR>
<H1><A NAME="REQUIREMENT">REQUIREMENT</A></H1>
<P>
You just need the DBI and DBD::Oracle perl module to be installed
<P>
<HR>
<H1><A NAME="PUBLIC_METHODS">PUBLIC METHODS</A></H1>
<P>
<HR>
<H2><A NAME="new_HASH_OPTIONS">new HASH_OPTIONS</A></H2>
<P>
Creates a new Ora2Pg object.
<P>
Supported options are:
<P>
<PRE> - datasource : DBD datasource (required)
- user : DBD user (optional with public access)
- password : DBD password (optional with public access)
</PRE>
<P>
Attempt that this list should grow a little more because all initialization
is done by this way.
<P>
<HR>
<H2><A NAME="export_sql_FILENAME">export_sql FILENAME</A></H2>
<P>
Print SQL conversion output to a filename or to STDOUT if no file is given.
<P>
<HR>
<H1><A NAME="PUBLIC_METHODS">PUBLIC METHODS</A></H1>
<P>
<HR>
<H2><A NAME="_init_HASH_OPTIONS">_init HASH_OPTIONS</A></H2>
<P>
Initialize a Ora2Pg object instance with a connexion to the Oracle
database.
<P>
<HR>
<H2><A NAME="_tables">_tables</A></H2>
<P>
This function is used to retrieve all table information.
<P>
Set the main hash of the database structure $self-&gt;{tables}. Keys are
the names of all tables retrieved from the current database. Each table
information compose an array associated to the table_info key as array
reference. In other way:
<P>
<PRE> $self-&gt;{tables}{$class_name}{table_info} = [(OWNER,TYPE)];
</PRE>
<P>
TYPE Can be TABLE, VIEW, SYSTEM TABLE, GLOBAL TEMPORARY, LOCAL TEMPORARY,
ALIAS, SYNONYM or a data source specific type identifier.
<P>
It also get the following informations in the DBI object to affect the main
hash of the database structure :
<P>
<PRE> $self-&gt;{tables}{$class_name}{field_name} = $sth-&gt;{NAME};
$self-&gt;{tables}{$class_name}{field_type} = $sth-&gt;{TYPE};
</PRE>
<P>
It also call these other private subroutine to affect the main hash of the
database structure :
<P>
<PRE> @{$self-&gt;{tables}{$class_name}{column_info}} = &amp;_column_info($self, $class_name);
@{$self-&gt;{tables}{$class_name}{primary_key}} = &amp;_primary_key($self, $class_name);
@{$self-&gt;{tables}{$class_name}{unique_key}} = &amp;_unique_key($self, $class_name);
@{$self-&gt;{tables}{$class_name}{foreign_key}} = &amp;_foreign_key($self, $class_name);
</PRE>
<P>
<HR>
<H2><A NAME="_get_sql_data">_get_sql_data</A></H2>
<P>
Returns a string containing the entire SQL Schema definition compatible
with PostgreSQL
<P>
<HR>
<H2><A NAME="_sql_type_INTERNAL_TYPE_LENGTH">_sql_type INTERNAL_TYPE LENGTH</A></H2>
<P>
This function return the PostgreSQL datatype corresponding to the Oracle
internal type.
<P>
<HR>
<H2><A NAME="_column_info_TABLE">_column_info TABLE</A></H2>
<P>
This function implements a Oracle-native column information.
<P>
Return a list of array reference containing the following informations for
each column the given a table
<P>
[( column name, column type, column length, nullable column, default value
)]
<P>
<HR>
<H2><A NAME="_primary_key_TABLE">_primary_key TABLE</A></H2>
<P>
This function implements a Oracle-native primary key column information.
<P>
Return a list of all column name defined as primary key for the given
table.
<P>
<HR>
<H2><A NAME="_unique_key_TABLE">_unique_key TABLE</A></H2>
<P>
This function implements a Oracle-native unique key column information.
<P>
Return a list of all column name defined as unique key for the given table.
<P>
<HR>
<H2><A NAME="_foreign_key_TABLE">_foreign_key TABLE</A></H2>
<P>
This function implements a Oracle-native foreign key reference information.
<P>
Return a list of hash of hash of array reference. Ouuf! Nothing very
difficult. The first hash is composed of all foreign key name. The second
hash just have two key known as 'local' and remote' corresponding to the
local table where the foreign key is defined and the remote table where the
key refer.
<P>
The foreign key name is composed as follow:
<P>
<PRE> 'local_table_name-&gt;remote_table_name'
</PRE>
<P>
Foreign key data consist in two array representing at the same indice the
local field and the remote field where the first one refer to the second.
Just like this:
<P>
<PRE> @{$link{$fkey_name}{local}} = @local_columns;
@{$link{$fkey_name}{remote}} = @remote_columns;
</PRE>
<P>
<HR>
<H2><A NAME="_get_privilege">_get_privilege</A></H2>
<P>
This function implements a Oracle-native tables grants information.
<P>
Return a hash of all groups (roles) with associated users and a hash of
arrays of all grants on related tables.
<P>
<HR>
<H1><A NAME="AUTHOR">AUTHOR</A></H1>
<P>
Gilles Darold &lt;<A
HREF="mailto:gilles@darold.net">gilles@darold.net</A>&gt;
<P>
<HR>
<H1><A NAME="COPYRIGHT">COPYRIGHT</A></H1>
<P>
Copyright (c) 2001 Gilles Darold - All rights reserved.
<P>
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
<P>
<HR>
<H1><A NAME="BUGS">BUGS</A></H1>
<P>
This perl module is in the same state as my knowledge regarding database,
it can move and not be compatible with older version so I will do my best
to give you official support for Ora2Pg. Your volontee to help construct it
and your contribution are welcome.
<P>
<HR>
<H1><A NAME="SEE_ALSO">SEE ALSO</A></H1>
<P>
<EM>DBI</EM>, <A HREF="/DBD/Oracle.html">DBD::Oracle</A>
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