PDO对mysql数据库相关操作
欢迎进入Linux社区论坛,与200万技术人员互动交流 >>进入 PDO是一个"数据库访问抽象层",作用是统一各种数据库的访问接口,与mysql和mysqli的函数库相比,PDO让跨数据库的使用更具有亲和力:与ADODB和MDB2相比,PDO更高效。 目前而言,实现"数据库抽象层"任重
欢迎进入Linux社区论坛,与200万技术人员互动交流 >>进入
PDO是一个"数据库访问抽象层",作用是统一各种数据库的访问接口,与mysql和mysqli的函数库相比,PDO让跨数据库的使用更具有亲和力:与ADODB和MDB2相比,PDO更高效。
目前而言,实现"数据库抽象层"任重而道远,使用PDO这样的"数据库访问抽象层"是一个不错的选择。
一。PDO基本函数库
PDO->beginTransaction() 标明回滚起始点
PDO->commit 标明回滚结束点,并执行SQL
PDO->__construct 建立一个PDO链接数据库的实例
PDO->errorCode 获取错误码
PDO->errorInfo 获取错误的信息
PDO->exec 处理一条SQL语句,并返回所影响的条目数
PDO->getAttribute 获取一个"数据库连接对象"的属性
PDO->getAvailableDrivers 获取有效的PDO驱动器名称
PDO->lastInsertId 获取写入的最后一条数据的主键值
PDO->prepare 生成一个"查询对象"
PDO->query 处理一条SQL语句,并返回一个"PDOStatement"
PDO->quote 为某个SQL中的字符串添加引号
PDO->rollBack 执行回滚
PDO->setAttribute 为一个"数据库连接对象"设定属性
二。PDO对mysql数据库相关操作
修改php.ini配置文件
1、找到与pdo相关的所有扩展
2、去掉pdo扩展前所有分号
3、重启apache服务
查询操作,select查询语句
一种方式:
$url = "mysql:host=主机地址;dbname=库名"; //连接数据库的参数
$user = "用户名";
$pwd = "密码";
$conn = new PDO($url,$user,$pwd); //连接数据库
$conn->query("set names utf8"); //设置编码
$st = $conn->query("select查询语句"); //执行select查询语句,返回数据库操纵对象statement
$rs = $st->fetchAll(); //获得结果集,结果集就是一个二维数组
//显示所有记录
foreach($rs as $value)
{
echo $value["字段名|列序号"];
}
//关闭数据库
unset($rs);
unset($st);
unset($conn);
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