In Hibernate, you can customize table and column names using JPA annotations such as @Table and @Column. These annotations allow you to define how your entity classes map to the database tables and columns. Here’s how you can do it:

Customize the Table Name

To specify a custom table name, use the @Table annotation on the class level. You define the table name by setting the name attribute of the @Table annotation.

import jakarta.persistence.Entity;
import jakarta.persistence.Table;

@Entity
@Table(name = "custom_table_name")
public class MyEntity {
    // Other fields and methods
}

In this example, the associated database table for the MyEntity class will be named custom_table_name.

Customize the Column Names

To customize column names, use the @Column annotation on the field or property. You can specify the name of the column by setting the name attribute of the annotation.

import jakarta.persistence.Entity;
import jakarta.persistence.Id;
import jakarta.persistence.Column;

@Entity
public class MyEntity {

    @Id
    private Long id;

    @Column(name = "custom_column_name")
    private String myField;

    // Getters and Setters
}

Here, the myField field will map to the column custom_column_name in the database.

Complete Example

Below is a complete example demonstrating both:

import jakarta.persistence.Entity;
import jakarta.persistence.Id;
import jakarta.persistence.Table;
import jakarta.persistence.Column;

@Entity
@Table(name = "custom_table_name")
public class MyEntity {

    @Id
    private Long id;

    @Column(name = "custom_column_name")
    private String customField;

    @Column(name = "date_of_creation", nullable = false, unique = true)
    private String creationDate;

    // Getters and Setters
}

• The @Table annotation maps the class to a custom table name (custom_table_name).
• The @Column annotation maps the fields to custom column names (custom_column_name and date_of_creation).
• Optional attributes like nullable, unique, length, etc., allow further customization.

Notes

1. Default Naming: If you omit the @Table or @Column annotations, Hibernate will use default naming strategies (usually camelCase names are converted to snake_case for the database).
2. Schema or Catalog: You can also specify a schema or catalog in the @Table annotation:

   @Table(name = "custom_table_name", schema = "my_schema")
   

3. Column Options: The @Column annotation includes additional options like:
   • nullable: Whether the column allows nulls.
   • unique: Whether the column should have a unique constraint.
   • length: The length of the column (useful for VARCHAR columns).
   • precision and scale: For DECIMAL and NUMERIC columns.

This level of customization gives you precise control over how your Java entities are mapped to database tables and columns.