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POdjango adding a ManyToMany field/table to existing schema, related_name error
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  1. POdjango adding a ManyToMany field/table to existing schema, related_name error
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    copied!<p>I have an existing project with models (Users and Books). I would like to add a ManyToMany(M2M) field to the existing model Books, but the syncbb command does not do this.</p> <p>Details: Books already has a FK field that maps to User, and I want to add a new M2M field (readers) that also maps to User. As you know, Django's syncdb only cares about tables, so adding a normal field is easy, but a M2M requires a new join table (app_books_user), so shouldn't syncdb cmd add this like any other new table? It created my other joined table for the Book's 'sellers' field.</p> <p>When I ran syncdb, I initially received an error instructing me to use the 'related_name' argument to help differentiate the two references to User. I added those. However, when I run syncdb again, it does not create the new join table (but it's now error-free). The new field exists when I view it via the Shell, but can't use it b/c the join table doesn't exist. I looked at the sql code via 'sqlall' cmd and it prints out the SQL for the new table, but it doesn't get executed.</p> <p>What am I missing? Should I just force the SQL (from the sqlall) via my database browser? Will that have any repercussions? Code follows:</p> <p>Models.py</p> <pre><code>from django.contrib.auth.models import User class Seller(models.Model): ... class Books(models.Model): name=models.CharField(max_length=50) author=models.ForeignKey(User, related_name='creator') readers=models.ManyToManyField(User, blank=True, related_name='viewers') sellers=models.ManyToManyField(Seller) </code></pre> <p>Thank you</p>
 

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