How do I search a db field for a the string after a "#" and add it to another db field in django
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I want to have a content entry block. When a user types #word or #blah in a field, I want efficiently search that field and add the string right after the "#" to a different field as a n entry in a different table. Like what Twitter does. This would allow a user to sort by that string later.

I believe that I would do this as a part of the save method on the model, but I'm not sure. AND, if the #blah already exists, than the content would belong to that "blah"

Can anyone suggest samples of how to do this? This is a little beyond what I'm able to figure out on my own.

Thanks!