CI框架如何在控制器里面链接数据库.然后执行SQL语句

在conf的自动加载，开启database自动加载，配置好数据库账号密码等，然后在控制器中如下：

$userInfo = $this->db->get('user')//user为user表名

或者

$query = "select * from user"

$this->db->query($query)

<?php

$mysql_server_name='localhost'

$mysql_username='root'

$mysql_password='12345678'

$mysql_database='mycounter'

$conn=mysql_connect($mysql_server_name,$mysql_username,$mysql_password,$mysql_database)

$sql='CREATE DATABASE mycounter DEFAULT CHARACTER SET gbk COLLATE gbk_chinese_ci

'

mysql_query($sql)

$sql='CREATE TABLE `counter` (`id` INT(255) UNSIGNED NOT NULL AUTO_INCREMENT ,`count` INT(255) UNSIGNED NOT NULL DEFAULT 0,PRIMARY KEY ( `id` ) ) TYPE = innodb'

mysql_select_db($mysql_database,$conn)

$result=mysql_query($sql)

//echo $sql

mysql_close($conn)

echo "Hello!数据库mycounter已经成功建立！"

---