java之jdbc_採用PreparedStatement刪除數據

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import java.sql.*;
import java.text.*;
import java.util.*;
//採用PreparedStatement刪除數據
public class DeleteTest02 {
    public static void main(String[] args) {
        if (args.length != 1) {
            throw new IllegalArgumentException("參數非法，正確使用爲InsertTest01 ...");
        }

        Connection conn = null;
        PreparedStatement pstmt = null;
        try {
            //第一步，加載數據庫驅動，不一樣的數據庫驅動程序不同
            Class.forName("oracle.jdbc.driver.OracleDriver");
            //第二部，獲得數據庫鏈接
            String dburl = "jdbc:oracle:thin:@localhost:1521:orcl";
            //String dburl = "jdbc:oracle:thin:@192.168.21.1:1521:orcl";
            //String dburl = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
            String userName = "system";
            String password = "wanwan";
            conn = DriverManager.getConnection(dburl, userName, password);
            //System.out.println(conn);

            //取得輸入參數
            int empno = Integer.parseInt(args[0]);

            //第三步，建立Statement，執行SQL語句
            //採用佔位符的方式
            //最好將比較複雜的sql調通，再將sql語句和程序相結合，進行連調
            String sql = "delete from enp where empno = ?";



            pstmt = conn.prepareStatement(sql);
            //爲佔位符賦值
            pstmt.setInt(1, empno);

            pstmt.executeUpdate();

            System.out.println("刪除員工成功， 員工編號：【"+ empno +"】");

        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            //注意關閉原則：從裏到外
            try {
                if (pstmt != null) {
                    pstmt.close();
                }
                if (conn != null) {
                    conn.close();
                }
            } catch(SQLException e) {

            }

        }
    }
}