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标题: 【转载】MySQL 查询数据（下） [打印本页]

作者: 简简单单 时间: 2017-2-10 11:00
标题: 【转载】MySQL 查询数据（下）
实例

以下实例使用MYSQL_NUM参数显示数据表runoob_tbl的所有记录:

<?php$dbhost = 'localhost:3036';$dbuser = 'root';$dbpass = 'rootpassword';$conn = mysql_connect($dbhost, $dbuser, $dbpass);if(! $conn ){ die('Could not connect: ' . mysql_error());}$sql = 'SELECT runoob_id, runoob_title, runoob_author, submission_date FROM runoob_tbl';mysql_select_db('RUNOOB');$retval = mysql_query( $sql, $conn );if(! $retval ){ die('Could not get data: ' . mysql_error());}while($row = mysql_fetch_array($retval, MYSQL_NUM)){ echo "Tutorial ID :{$row[0]} ". "Title: {$row[1]} ". "Author: {$row[2]} ". "Submission Date : {$row[3]} ". "-------------------------------- ";}echo "Fetched data successfully\n";mysql_close($conn);?>

以上三个实例输出结果都一样。

内存释放在我们执行完SELECT语句后，释放游标内存是一个很好的习惯。。可以通过PHP函数mysql_free_result()来实现内存的释放。
以下实例演示了该函数的使用方法。
实例尝试以下实例:
<?php$dbhost = 'localhost:3036';$dbuser = 'root';$dbpass = 'rootpassword';$conn = mysql_connect($dbhost, $dbuser, $dbpass);if(! $conn ){ die('Could not connect: ' . mysql_error());}$sql = 'SELECT runoob_id, runoob_title, runoob_author, submission_date FROM runoob_tbl';mysql_select_db('RUNOOB');$retval = mysql_query( $sql, $conn );if(! $retval ){ die('Could not get data: ' . mysql_error());}while($row = mysql_fetch_array($retval, MYSQL_NUM)){ echo "Tutorial ID :{$row[0]} ". "Title: {$row[1]} ". "Author: {$row[2]} ". "Submission Date : {$row[3]} ". "-------------------------------- ";}mysql_free_result($retval);echo "Fetched data successfully\n";mysql_close($conn);?>

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