I need to add a NOT NULL column to an existing (populated) table that will be a foreign key to another table. This brings about two problems:
I have some models all linked together in memory (parent:child:child:child) and saved at the same time by saving the top-most parent.This works fine.
After having changed around my mappings a bit ( see my other question about cascade-delete for reasons) , i tried inserting a completely new object and all its subclasses.
Let\'s say I\'ve got a model and it has a foreign key to another one. class ModelA(models.Model): field = models.CharField(max_length=100)
i have a process to move rows from one database to another. Because of some circular foreign key reference chains i cannot remove the rows from the old database, nor can i insert them into the new dat
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I was migrating mysql database to postgres and stumbled across the following block in DDL (Note: This is what I got from mysqldump):
Steps: I want a registered user to be able to insert values into a table. Those values would only be able to be seen or edited by the user. (a few rows)
I have a table which has one column as a foreign key joining to another table. It\'s a cricket question where I have a table called Fixtures and another called Inning.
Delete any record of them will report an error like this: ERROR 1451 (23000): Cannot delete or update a parent row: a foreign key
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