Question

java中怎样对mysql数据库查询

Answer 1

import java.sql.Connection;  
import java.sql.DriverManager;  
import java.sql.ResultSet;  
import java.sql.ResultSetMetaData;  
import java.sql.Statement;  
import java.util.Hashtable;  
  
  
public class GetDBFiled {  
    public static void conn() {  
        String driver = "com.mysql.jdbc.Driver";  
        String url = "jdbc:mysql://localhost:3306/databaseName";  
        String user = "root";  
        String password = "密码";  
        try {  
            Class.forName(driver);  
            Connection conn = DriverManager.getConnection(url, user, password);  
            if (!conn.isClosed()) {  
                String sql = "select * from pic";  
                System.out.println("Succeeded connecting to the Database!");  
                Statement statement =conn.createStatement();  
                ResultSet rs = statement.executeQuery(sql);  
                if (rs.next()) {  
                    // 得到ResultSetMetaData  
                    ResultSetMetaData rsmd = rs.getMetaData();  
                    System.out.println(rsmd.getColumnCount());  
                    for (int i = 1; i <= rsmd.getColumnCount(); i++) {  
                        Hashtable hst = new Hashtable();  
                        // 把字段名放入Name  
                        String name = String.valueOf(rsmd.getColumnLabel(i));  
                        hst.put("Name", name);  
                        // 把字段类型放入Type  
                        String type = String.valueOf(rsmd.getColumnType(i));  
                        hst.put("Type", type);  
                        System.out.println(hst.get("Name")+"  "+hst.get("Type"));  
                    }  
                }  
            }  
        } catch (Exception e) {  
  
            System.out.println("出现异常");  
        }  
  
    }  
}

Answer 2

import java.sql.*;

public class MySqlJDBC {
public static void main(String args[]) {
try {
Class.forName("com.mysql.jdbc.Driver"); // 加载对应 JDBC驱动程序
System.out.println("Success loading Mysql Driver!");
} catch (Exception e) {
System.out.print("Error loading Mysql Driver!");
e.printStackTrace();
}
try {
Connection connect = DriverManager.getConnection(
"jdbc:mysql://localhost:4706/sdkcc", "root", "123456");
// 连接URL为 jdbc:mysql//服务器地址/数据库名
// 后面的2个参数分别是登陆用户名和密码
System.out.println("Success connect Mysql server!");
Statement stmt = connect.createStatement();
ResultSet rs = stmt.executeQuery("select * from actor");
while (rs.next()) {
System.out.println(rs.getString("actor_id") + "\t"
+ rs.getString("first_name") + "\t" + "\t"
+ rs.getString("last_name") + "\t"
+ rs.getString("last_update"));
}
} catch (Exception e) {
System.out.print("get data error!");
e.printStackTrace();
}
}
}

也可以自己上网查下资料，这很容易查到！