在该问题中,我们需要将AspNetUsers表中的Id字段从字符串类型更改为整数类型,但是在保存更改后,我们会收到“无法将NULL插入到列'Id'表中”的错误消息。这是因为在更改字段类型后,我们需要为旧记录中的每个行添加一个Id值。
以下是解决方法的示例代码(请注意,这是一种简单的方法,根据你的需求和实际情况,你可能需要采用不同的方法):
ALTER TABLE AspNetUsers ADD Id_new INT IDENTITY(1,1);
WITH UserCTE AS ( SELECT Id_new, ROW_NUMBER() OVER (ORDER BY Id) AS RowNum FROM AspNetUsers ) UPDATE AspNetUsers SET Id_new = UserCTE.Id_new FROM AspNetUsers INNER JOIN UserCTE ON AspNetUsers.Id = UserCTE.RowNum
UPDATE AspNetRoles SET UserId = (SELECT Id_new FROM AspNetUsers WHERE AspNetUsers.Id = AspNetRoles.UserId);
UPDATE AspNetUserRoles SET UserId = (SELECT Id_new FROM AspNetUsers WHERE AspNetUsers.Id = AspNetUserRoles.UserId);
ALTER TABLE AspNetUsers DROP COLUMN Id;
EXEC sp_rename 'AspNetUsers.Id_new', 'Id', 'COLUMN'
这些代码会将旧的AspNetUsers.Id列替换为新的AspNetUsers.Id_new列,并将