Django: You are trying to add a non-nullable field 'name' to mainnav without a default; we can't do that (the database needs something to populate existing rows).

【Django: You are trying to add a non-nullable field 'name' to mainnav without a default; we can't do that (the database needs something to populate existing rows).】的更多相关文章

$ python manage.py makemigrations You are trying to add a non-nullable field 'name' to course without a default; we can't do that (the database needs something to populate existing rows). Please selec

问题: $ python manage.py makemigrationsYou are trying to add a non-nullable field 'name' to course without a default; we can't do that (the database needs something to populate existing rows).Please select a fix:1) Provide a one-off default now (will b…

Django model ：add a non-nullable field 'SKU' to product without a default; we can't do that

You are trying to add a non-nullable field 'SKU' to product without a default; we can't do that (the database needs something to populate existing rows). Please select a fix: 1) Provide a one-off default now (will be set on all existing rows) 2) Quit…

Django数据库操作中You are trying to add a non-nullable field 'name' to contact without a default错误处理

name = models.CharField(max_length=50) 执行:python manage.py makemirations出现以下错误: You are trying to add a non-nullable field 'name' to contact without a default; we can't do that (the database needs something to populate existing rows). Please select a…

Django | 模型类变更后生成迁移文件，报错:You are trying to add a non-nullable field 'BookName' to BookInfo without a default....

报错: You are trying to add a non-nullable field 'BookName' to BookInfo without a default; we can't do that (the database needs something to populate existing rows). Please select a fix: 1) Provide a one-off default now (will be set on all existing row…

python manage.py makemigrat Please select a fix: 1) Provide a one-off default now (will be set on all existing rows with a null value for this column) 2) Quit, and let me add a default in models.py

更新models字段出现的问题: $ python manage.py makemigrations None You are trying to add a non-nullable field 'file_type' to filejinja without a default; we can't do that (the database needs something to populate existing rows). Please select a fix: ) Provide…

How do I add a Foreign Key Field to a ModelForm in Django?

What I would like to do is to display a single form that lets the user: Enter a document title (from Document model) Select one of their user_defined_code choices from a drop down list (populated by the UserDefinedCode model) Type in a unique_code (s…