Changing the data type of a model object in sleep mode after creation

Question

I am studying hibernation. I got a little confused with the hbm2dll.auto update property. Changing the data type of a model object does not change the table data type in mysql.

First, I created a User Pojo with userId as an int data type. I originally created the hbm2dll property as CREATE.

@Entity(name="user")
public class User {
    @Id
    private int userid; 
    private String username;
    ....

}

To save the data, firstly I created a custom object as shown below and saved using sessionFactory.

User user = new user();
     user.setUserid(1);
     user.setUsername("First User");

Due to the above effort, a user table has been created in which the user data is int.

But later I changed the user data type pojos userid to a string.

I also changed the hbm2ddl property to update.

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Answer 1

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Answer 2

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Answer 3

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Answer 4

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