Remove object from has_many but don't delete the original record in Rails?

问题

I have this:

Post.paragraphs << new_paragraph

And I need to remove paragraph by id = 3, so the following deletes the record completely:

Post.paragraphs.find(paragraph_id).destroy
# or
Post.paragraphs.find(paragraph_id).delete

I just need to remove a paragraph from has_many association. I tried to use delete and destroy. Both methods completely delete records from the associated tables. How can I just remove them from the "container"?

回答1:

You should not use the delete method on the Paragraphobject, but instead use the delete method of paragraphs relation, like this:

post.paragraphs.delete(Paragraph.find(paragraph_id))

来源：https://stackoverflow.com/questions/25660419/remove-object-from-has-many-but-dont-delete-the-original-record-in-rails