1. jdbc : java数据库连接技术
2.主要用到的类及接口
Class | Driver | ManagerDriver | Connection | Statement | PreparedStatement | CallableStatement | ResultSet | SQLException |
3.JDBC批量处理
4.JDBC数据流
blob、clob
5.对象
statement:boolean execute (String SQL)
: 如果可以检索到ResultSet
对象,则返回一个布尔值true
; 否则返回false
preparedstatement: 可以使用输入参数的SQL语句, setXXX()
方法将值绑定到参数
CallableStatement:registerOutParameter(3, java.sql.Types.INTEGER);
6.ResultSet
prepareStatement(String SQL, int RSType, int RSConcurrency);
类型:ResultSet.TYPE_SCROLL_SENSITIVE
并发:ResultSet.CONCUR_UPDATABLE
- updateString(int columnIndex, String s) ;updateRow()
7.简单示例
package com.rong.web; import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement; public class Test1 { /**
* @author 容杰龙
*
*/
public static void main(String[] args) {
Connection conn = null;
Statement cs = null;
ResultSet rs = null;
try {
// 加载MySQL数据库驱动
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/rjl";
String user = "root";
String password = "123123";
// 获取连接对象的三种方式
conn = DriverManager.getConnection(url, user, password); // url="jdbc:mysql://localhost:3306/rjl?user=root&password=123123";
// conn =DriverManager.getConnection(url); // Properties properties=new Properties();
// properties.setProperty("user", "root");
// properties.setProperty("password", "123123");
// conn =DriverManager.getConnection(url, properties); // 创建语句对象
cs = conn.createStatement();
String sql = "select * from emp;";
// 执行语句
rs = cs.executeQuery(sql);
while (rs.next()) {
// 获取结果集中的数据
System.out.println(rs.getString("ename"));
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// 关闭资源
try {
if (rs != null) {
rs.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
if (cs != null) {
cs.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
if (conn != null) {
conn.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
} } }