Updating join fields in an ORM command

Posted by Jono on Stack Overflow See other posts from Stack Overflow or by Jono
Published on 2010-06-11T19:12:14Z Indexed on 2010/06/11 19:32 UTC
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update

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join

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object-relational-mapping

I have a question about object relational updates on join fields.

I am working on a project using codeigniter with datamapper dmz. But I think my problem is with general understanding of ORMs. So fell free to answer with any ORM you know.

I have two tables, Goods and Tags. One good can have many tags. Everything is working, but I am looking for a way to merge tags. Meaning I decide I want to remove tag A and instead have everything that is tagged by it, now be tagged by tag B.

I only have models for the goods and the tags. There is no separate model for the join relationship, as I believe these ORMs were designed to work.

I know how to delete a tag. But I dont know how to reach into the join table to redirect the references since there is no model for the join table. I would rather use the ORM then issuing a raw SQL command.

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