Postgres, unless I am terribly mistaken, uses sequences to generate IDs. Class::DBI requires that you identify the sequences, if used.

  $class->sequence( $sequence_name );
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For your code, that should probably be something like the following in your base class:

  Gallery::Image->sequence('gallery_images_id_seq');
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I also see that you're calling $class->commit without calling $class->dbi_commit. If you have transactions enabled, you'll have to call the latter after the former as the commit() method has nothing to do with committing a transaction. You may wish to read the docs about this issue. It's been a source of confusion here at work (and I stills screw it up).

Cheers,
Ovid

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