Get the values of the columns automatically increment when Insert a record using JDBC

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1- Problem

In some databases, the ID column of a table can be of type of which values automatically increase. Whenever you insert a record into a table, the value of this column is assigned by the database. You can not proactively assign a value to it. Your question in this case is how to obtain the ID of the inserted record.
In addition, some columns may not be invoilved in your Insert statement, in which case their values are assigned by default by a database. You want to get these values without creating a more query statement.

PostGres

In  PostGres, the column with Serial type will have values automatically increasing by database.
** Employees (PostGres) **
CREATE TABLE Employees
(
    ID serial NOT NULL,
    Full_Name character varying(50) NOT NULL,
    Gender character varying(1) default 'M' NOT NULL,
    Hire_Date date NOT NULL,
    PRIMARY KEY (ID)
);
 

MySQL

In  MySQL, for a column to have automatically increasing value, it must be assigned the  "Auto_Increase" attribute .
** Employees (MySQL) **
CREATE TABLE Employees
(
    ID Int Auto_Increase NOT NULL,
    Full_Name Varchar(50) NOT NULL,
    Gender Varchar(1) default 'M' NOT NULL,
    Hire_Date date NOT NULL,
    PRIMARY KEY (ID)
);

2- Get the value of ID column inserted

When you use JDBC to   Insert a record to the  database. The  ID column can not be involved in the  Insert statement. The position of ID column is defined by the design of such table. The first column has index 1 and the second column has index 2,...
GeneratedIDValueExample.java
package org.o7planning.tutorial.jdbc.others;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.o7planning.tutorial.jdbc.ConnectionUtils;

public class GeneratedIDValueExample {

	public static void main(String[] args) throws ClassNotFoundException, SQLException {
		// Get a connection
		Connection conn = ConnectionUtils.getMyConnection();

		// Employees (id, full_name, gender, hire_date)
		// ID: Auto Increase
		String sql = "Insert into Employees " //
				+ " (full_name, gender, hire_date) " //
				+ " values " //
				+ " (?, ?, ?)";

		// Create a PreparedStatement object.
		PreparedStatement pstm = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);

		pstm.setString(1, "Tran");
		pstm.setString(2, "M");
		pstm.setDate(3, new java.sql.Date(System.currentTimeMillis()));

		// Execute!
		pstm.execute();

		ResultSet rs = pstm.getGeneratedKeys();

		int idValue = 0;
		if (rs.next()) {
			// Value of ID (Index 1 by table design).
			idValue = rs.getInt(1);
		}

		System.out.println("ID value: " + idValue);

	}
}
The index of the ID column of the table isn't  probably  1 (depending on the design of the table). In this case, you best access its value by name.
GeneratedIDValueExample2.java
package org.o7planning.tutorial.jdbc.others;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.o7planning.tutorial.jdbc.ConnectionUtils;

public class GeneratedIDValueExample2 {

	public static void main(String[] args) throws ClassNotFoundException, SQLException {

		Connection conn = ConnectionUtils.getMyConnection();

		// Employees (id, full_name, gender, hire_date)
		// ID: Auto Increase
		String sql = "Insert into Employees " //
				+ " (full_name, gender, hire_date) " //
				+ " values " //
				+ " (?, ?, ?)";

		// Create a PreparedStatement object.
		PreparedStatement pstm = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);

		pstm.setString(1, "Tran");
		pstm.setString(2, "M");
		pstm.setDate(3, new java.sql.Date(System.currentTimeMillis()));

		// Execute!
		pstm.execute();

		ResultSet rs = pstm.getGeneratedKeys();

		int idValue = 0;
		if (rs.next()) {
			// Value of ID.
			// Note, for some DB, column names are case sensitive.
			// (eg Postgres, column names are always lowercase).
			idValue = rs.getInt("id");
		}

		System.out.println("ID value: " + idValue);

	}
}

3- Get the values of many columns inserted 

Some columns may not participate in your Insert statement . Their values are assigned by the database. You can get their values without creating a query statement.
GetGeneratedValueExample2.java
package org.o7planning.tutorial.jdbc.others;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.o7planning.tutorial.jdbc.ConnectionUtils;

public class GetGeneratedValueExample2 {

	public static void main(String[] args) throws ClassNotFoundException, SQLException {

		Connection conn = ConnectionUtils.getMyConnection();

		// Employees (id, full_name, gender, hire_date)
		// ID: Auto Increase
		// gender: Default
		String sql = "Insert into Employees " //
				+ " (Full_Name,  Hire_Date) " //
				+ " values " //
				+ " (?,  ?)";

		// Create a PreparedStatement object.
		// And register the output parameters by name ("id", "gender", "hire_date")
		PreparedStatement pstm = conn.prepareStatement(sql, new String[] { "id", "gender", "hire_date" });

		pstm.setString(1, "Tran");
		pstm.setDate(2, new java.sql.Date(System.currentTimeMillis()));

		// Execute!
		pstm.execute();

		ResultSet rs = pstm.getGeneratedKeys();

		int idValue = 0;
		String gender = null;
		java.sql.Date hireDate = null;
		if (rs.next()) {
			idValue = rs.getInt("ID");
			gender = rs.getString("Gender");
			hireDate = rs.getDate("Hire_Date");
		}

		System.out.println("ID value: " + idValue + " Gender: " + gender + ", Hidedate: " + hireDate);

	}
}

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