如何更改“ id”字段的初始值？

Question

I have a User model, which generated the bellow table:

in it the id is increase from 1 .

I have used my system in a spell, now I want to change the id of some user instance and start at 10000 .

in the database I can not change, it will report error:

Cannot delete or update a parent row: a foreign key constraint fails (`qy`.`usermanage_user_groups`, CONSTRAINT `usermana_user_id_53f44f10_fk_qy_adm` FOREIGN KEY (`user_id`) REFERENCES `usermanage_user` (`id`))

Is it possible to change the id ? if there is some related factors, how can I solved it one by one, such as usermanage_user_groups ?

Answer 1

The id field is an automatic primary key field added by Django since you did not provide the primary_key=True property.

NOTE

Now, as the comments says you probably should not have to change the behavior of that field since it guarantee uniqueness throughout your data. See linked documentation for more information.

Considering you understood that by now, there is two possiblities for you in my opnion.

Preferred solution I think

1) Add a custom AutoField and start it at 10000 and it will then update accordingly.

Hack version

2) Add a user with an id of 9999 in your database. This will result in auto-incrementing your id field according to this new value. It won't fill the values in between.

Answer 2

You can setup sequence start from 10000 in your database. Also may trying manually add user with id 9999 through db manager.

Answer 3

I sort of understand what you want to achieve, but I'm not sure if you want to retain the existing user data across your tables including user, usermanage_user, usermanage_user_groups;

Meaning, Do you simply want to replace user_id from [1, 2, 3, 4, ......25] to [10000, 10001, 10002, 10004, ...... 10025] for the existing users?

1] If yes, then manipulating tables in DB to safely update ID in all the referred table is one way. I can give a better solution here, if you share your schema structures / django models.

2] If no, you can simply set AUTO_INCREMENT to 10000, so that the following newly added users begin with 10000+

 `ALTER TABLE User AUTO_INCREMENT = 10000;`