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Spring Data JPA - @Table Annotation

Last Updated : 28 Mar, 2025

Spring Data JPA is a powerful framework that simplifies database interactions in Spring Boot applications. The @Table annotation in JPA (Java Persistence API) is used to specify the table name in the database and ensure proper mapping between Java entities and database tables. This is especially useful when:

• The database table name differs from the entity class name.
• We need to ensure uniqueness across multiple columns.
• Working with multi-schema databases (for example, legacy systems).

In this article, we will explore how to use the @Table annotation in Spring Data JPA with an example.

The @Table annotation in JPA is used to define the database table mapping for an entity. It allows customization of:

• Table name (default is the entity class name)
• Catalog and schema (useful for multi-database environments)
• Unique constraints on specific columns

Syntax:

import jakarta.persistence.*;

@Entity

@Table(name = "student") // Custom table name
public class Student {
// Fields and methods
}

In this example, the table is explicitly named "student" instead of relying on the default entity name.

The @Table annotation provides the following attributes:

Attribute

Description

name

It defines the table name (default: entity class name).

catalog

It specifies the database catalog.

schema

It defines the database schema.

uniqueConstraints

It enforces unique constraints on specific columns.

@Entity
@Table(name = "EMPLOYEE", uniqueConstraints = { @UniqueConstraint(columnNames = "email") })
public class Employee {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @Column(nullable = false, unique = true)
    private String email;
}

In this example, the email field must be unique across all rows in the EMPLOYEE table.

• Go to Spring Initializr
• Fill in the details:
  • Project: Maven
  • Language: Java
  • Spring Boot Version: 3.x.x (or latest stable version)
  • Packaging: JAR
  • Java Version: 17 or later
  • Dependencies: Spring Web, Spring Data JPA, MySQL Driver

Click on Generate, download, and extract the project.

• Extract the zip file.
• Open your preferred IDE (IntelliJ, Eclipse, VS Code). Here, we are using IntelliJ IDE.
• Now open a suitable IDE and then go to File > New > Project from Existing Sources and select pom.xml.
• Ensure pom.xml is recognized and dependencies are downloaded.

Adding the necessary properties in the application.properties file. (mapping is the database name)

spring.datasource.url=jdbc:mysql://localhost:3306/mapping

spring.datasource.username=root

spring.datasource.password=your_password

spring.jpa.hibernate.ddl-auto=update

Best Practice: Avoid hardcoding credentials. Use environment variables:

spring:

datasource:

username: ${DB_USER}

password: ${DB_PASS}

Create a model folder in the project folder and make a StudentInformation class.

StudentInformation.java:

package com.example.mapping.models;

import jakarta.persistence.*;

@Entity
@Table(name = "student")     // Custom table name
public class StudentInformation {
    
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int rollno;

    private String name;

    // Default constructor
    public StudentInformation() {}

    // Parameterized constructor
    public StudentInformation(int rollno, String name) {
        this.rollno = rollno;
        this.name = name;
    }

    // Getters and Setters
    public int getRollno() { 
        return rollno; 
        
    }
    public void setRollno(int rollno) { 
        this.rollno = rollno; 
        
    }

    public String getName() { 
        return name; 
        
    }
    public void setName(String name) { 
        this.name = name; 
        
    }
}

Run the main application class.

Database Output:

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