NAME

OpenPlugin::Datasource::DBI - DBI driver, used to create DBI database handles for the OpenPlugin::Datasource plugin

SYNOPSIS

 # Define the parameters for a database handle 'main' in the config file

 <datasource main>
    type          = DBI
    db_owner      =
    username      = webuser
    password      = urkelnut
    dsn           = host=localhost;database=urkelweb
    db_name       =
    driver        = mysql
    long_read_len = 65536
    long_trunc_ok = 0
 </datasource>

 # Request the datasource 'main':

 my $dbh = $OP->datasource->connect( 'main' );
 my $sth = $dbh->prepare( "SELECT * FROM urkel_fan" );
 $sth->execute;
 ...

DESCRIPTION

No, we do not subclass DBI with this. No, we do not override any of the DBI methods. Instead, we provide the means to connect to the database from one location using nothing more than a datasource name. This is somewhat how the Java Naming and Directory Interface (JNDI) allows you to manage objects, including database connections.

Note that if you are using it this should work flawlessly with Apache::DBI, and if you are using this on a different persistent Perl platform (say, PerlEx) then this module gives you a single location from which to retrieve database handles -- this makes using the BEGIN/END tricks ActiveState recommends in their FAQ pretty trivial.

METHODS

connect( $datasource_name, \%datasource_info )

Returns: A DBI database handle with the following parameters set:

 RaiseError:  1
 PrintError:  0
 ChopBlanks:  1
 AutoCommit:  1 (for now...)
 LongReadLen: 32768 (or as set in \%datasource_info)
 LongTruncOk: 0 (or as set in \%datasource_info)

The parameter \%datasource_info defines how we connect to the database.

  • dsn ($)

    The last part of a fully-formed DBI data source name used to connect to this database. Examples:

     Full DBI DSN:     DBI:mysql:webdb
     OpenPlugin DSN:   webdb
    
     Full DBI DSN:     DBI:Pg:dbname=web
     OpenPlugin DSN:   dbname=web
    
     Full DBI DSN:     DBI:Sybase:server=SYBASE;database=web
     OpenPlugin DSN:   server=SYBASE;database=web

    So the OpenPlugin DSN string only includes the database-specific items for DBI, the third entry in the colon-separated string. This third item is generally separated by semicolons and usually specifies a database name, hostname, packet size, protocol version, etc. See your DBD driver for what to do.

  • driver ($)

    What DBD driver is used to connect to your database? (Examples: 'Pg', 'Sybase', 'mysql', 'Oracle')

  • db_name ($) (optional)

    TODO: Will we keep this? Unsure...

    The name of your database -- only include if you want to 'share connections' among different websites and if you do not specify the database name in your dsn.

  • db_owner ($) (optional)

    Who owns this database? Only use if your database uses the database owner to differentiate different tables.

  • username ($)

    What username should we use to login to this database?

  • password ($)

    What password should we use in combination with the username to login to this database?

  • long_read_len ($) (optional)

    Set the LongReadLen value for the database handle (See DBI for information on what this means.) If not set this defaults to 32768.

  • long_trunc_ok (bool) (optional)

    Set the LongTruncOk value for the database handle (See DBI for information on what this means.) If not set this defaults to false.

  • trace_level ($) (optional)

    Use the DBI trace() method to output logging information for all calls on a database handle. Default is '0', which is no tracing. As documented by DBI, the levels are:

        0 - Trace disabled.
        1 - Trace DBI method calls returning with results or errors.
        2 - Trace method entry with parameters and returning with results.
        3 - As above, adding some high-level information from the driver
            and some internal information from the DBI.
        4 - As above, adding more detailed information from the driver.
            Also includes DBI mutex information when using threaded Perl.
        5 and above - As above but with more and more obscure information.

Any errors encountered will cause an exception to be thrown. The error message will generally be a connection error, meaning you cannot even connect to the database. This is generally a very serious error.

TO DO

Nothing known.

BUGS

None known.

SEE ALSO

Apache::DBI

DBI - http://www.symbolstone.org/technology/perl/DBI

PerlEx - http://www.activestate.com/Products/PerlEx/

COPYRIGHT

Copyright (c) 2001-2003 Eric Andreychek. All rights reserved.

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

AUTHORS

Eric Andreychek <eric@openthought.net>

Chris Winters <chris@cwinters.com>