[JAVA] Execute Update

1. executeQuery() : 리턴값 ResultSet, SELECT문에만 사용한다.
2. executeUpdate() : 리턴값 int, INSERT, UPDATE, DELETE문에 사용한다.

 

package database;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class OjdbcConnection {

	private static String driverName = "oracle.jdbc.driver.OracleDriver";
	private static String url = "jdbc:oracle:thin:@localhost:1521:XE";
	private static String user = "hr";
	private static String practiceuser = "practice";
	private static String password = "1234";
	
	static {
		
		try {
			Class.forName(driverName);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
	
	public static Connection getConnection() throws SQLException {
		return DriverManager.getConnection(url, user, password);
	}
}

package database;

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

public class J03_ExecuteUpdate {

	public static void main(String[] args) {

		// 자바에서 시퀀스도 사용할 수 있다.
		String query = "INSERT INTO coffee VALUES(coffee_id_seq.nextval, ?, ?)";
	
		try(
			Connection conn = OjdbcConnection.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(query);
			) {
			pstmt.setString(1, "Javachip ..");
			pstmt.setInt(2, 5500);
	
		// INSERT, UPDATE, DELETE는 SELECT와 다르게
		// executeUpdate() 메서드를 사용해야 한다.
		// 리턴값으로는 몇 행이 (추가/수정/삭제)되었는지 알려준다.
		int row = pstmt.executeUpdate();
		System.out.println(row + "행 추가되었습니다.");
		
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}