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HomeDatabaseMysql Tutorialphp 读取mysql数据库三种方法

mysql 读取数据库三种方法,需要的朋友可以参考下。

代码如下:

$dbh = @mysql_connect("localhost:3306","root","000000");
/* 定义变量dbh , mysql_connect()函数的意思是连接mysql数据库, "@"的意思是屏蔽报错 */
if(!$dbh){die("error");}
/* die()函数的意思是将括号里的字串送到浏览器并中断PHP程式 (Script)。括号里的参数为欲送出的字串。 */
@mysql_select_db("ok", $dbh);
/* 选择mysql服务器里的一个数据库,这里选的数据库名为 ok */
$q = "SELECT * FROM abc";
/* 定义变量q, "SELECT * FROM abc"是一个SQL语句,意思是读取表abc中的数据 */
?>


代码如下:

$rs = mysql_query($q, $dbh);
/* 定义变量 rs ,函数mysql_query()的意思是:送出 query 字串供 MySQL 做相关的处理或者执行.由于php是从右往左执行的
,所以,rs的值是服务器运行mysql_query()函数后返回的值 */
if(!$rs){die("Valid result!");}
echo "";
echo "";
while($row = mysql_fetch_row($rs)) echo "";
/* 定义量变(数组)row,并利用while循环,把数据一一写出来.
函数mysql_fetch_row()的意思是:将查询结果$rs单列拆到阵列变数中.
$row[0] 和 $row[1] 的位置可以换*/
echo "
ID Name
$row[0] $row[1]
";
?>


代码如下:

$rs = mysql_query($q, $dbh);
while($row = mysql_fetch_object($rs)) echo "$row->id $row->name
";
/* id和name可以换位置 */
?>


代码如下:

$rs = mysql_query($q, $dbh);
while($row = mysql_fetch_array($rs)) echo "$row[id] $row[name]
";
/* id和name可以换位置 */
?>


@mysql_close($dbh);
/* 关闭到mysql数据库的连接 */
?>
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