1.1 JDBC的CRUD操作之PreparedStatement的查询操作
1.1.1 查询操作代码实现
@Test
public void demo4(){
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try{
conn = JDBCUtils.getConnection();
String sql = "select * from user";
pstmt = conn.prepareStatement(sql);
rs = pstmt.executeQuery();
while(rs.next()){
System.out.println(rs.getInt("id")+" "+rs.getString("username")+" "+rs.getString("password")+" "+rs.getString("nickname"));
}
}catch(Exception e){
e.printStackTrace();
}finally{
JDBCUtils.release(rs, pstmt, conn);
}
}
- 已知表数据:
![在这里插入图片描述](https://img-blog.csdnimg.cn/20200926150751855.png#pic_center)
- 控制台输出:
![在这里插入图片描述](https://img-blog.csdnimg.cn/20200926150710256.png#pic_center)