在Java中获取数据库连接

Question

这是我的源代码。

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

public class DBConnect {

    public static void main(String[] args) {

        try {
            String host = "jdbc:derby://localhost:1527/Employee";
            String uName = "jayani";
            String uPass = "jayani";
            Connection con = DriverManager.getConnection(host, uName, uPass);
            Statement stmt = con.createStatement();
            String sql = "SELECT*FROM WORKERS";

            ResultSet rs = stmt.executeQuery(sql);

            while (rs.next()) {
                int id_col = rs.getInt("ID");
                String fname = rs.getString("FIRST_NAME");
                String lname = rs.getString("LAST_NAME");
                String job = rs.getString("JOB_TITLE");

                System.out.println(id_col + "" + fname + "" + lname + "" + job);

            }
        } catch (SQLException ex) {

            System.out.println(ex.getMessage());
        }
    }
}

在这里，我遇到了一个异常，例如“ executeQuery方法无法用于更新”。 什么是例外，我该如何解决。 谢谢。

Answer 1

您需要像这样使用executeQuery

    Statement stmt = null;
    String query = "select * from <tablename>";
    stmt = con.createStatement();
    ResultSet rs = stmt.executeQuery(query);