php MySQL 查询数据

以下为在MysqL数据库中查询数据通用的 SELECT 语法：

SELECT column_name,column_name
FROM table_name
[WHERE Clause]
[LIMIT N][ OFFSET M]

使用 MysqLi_fetch_array MysqLI_ASSOC 参数获取数据：

 

<?PHP
$dbhost = 'localhost:3306';  // MysqL服务器主机地址
$dbuser = 'root';            // MysqL用户名
$dbpass = '123456';          // MysqL用户名密码
$conn = MysqLi_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . MysqLi_error($conn));
}
// 设置编码，防止中文乱码
MysqLi_query($conn , "set names utf8");
 
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl';
 
MysqLi_select_db( $conn, 'RUNOOB' );
$retval = MysqLi_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . MysqLi_error($conn));
}
echo '<h2>菜鸟教程 MysqLi_fetch_array 测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = MysqLi_fetch_array($retval, MysqLI_ASSOC))
{
    echo "<tr><td> {$row['runoob_id']}</td> ".
         "<td>{$row['runoob_title']} </td> ".
         "<td>{$row['runoob_author']} </td> ".
         "<td>{$row['submission_date']} </td> ".
         "</tr>";
}
echo '</table>';
MysqLi_close($conn);
?>

使用 MysqLi_fetch_assoc 获取数据：

<?PHP
$dbhost = 'localhost:3306';  // MysqL服务器主机地址
$dbuser = 'root';            // MysqL用户名
$dbpass = '123456';          // MysqL用户名密码
$conn = MysqLi_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . MysqLi_error($conn));
}
// 设置编码，防止中文乱码
MysqLi_query($conn , "set names utf8");
 
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl';
 
MysqLi_select_db( $conn, 'RUNOOB' );
$retval = MysqLi_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . MysqLi_error($conn));
}
echo '<h2>菜鸟教程 MysqLi_fetch_assoc 测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = MysqLi_fetch_assoc($retval))
{
    echo "<tr><td> {$row['runoob_id']}</td> ".
         "<td>{$row['runoob_title']} </td> ".
         "<td>{$row['runoob_author']} </td> ".
         "<td>{$row['submission_date']} </td> ".
         "</tr>";
}
echo '</table>';
MysqLi_close($conn);
?>

使用 MysqLi_fetch_array MysqLI_NUM 参数获取数据：

<?PHP
$dbhost = 'localhost:3306';  // MysqL服务器主机地址
$dbuser = 'root';            // MysqL用户名
$dbpass = '123456';          // MysqL用户名密码
$conn = MysqLi_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . MysqLi_error($conn));
}
// 设置编码，防止中文乱码
MysqLi_query($conn , "set names utf8");
 
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl';
 
MysqLi_select_db( $conn, 'RUNOOB' );
$retval = MysqLi_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . MysqLi_error($conn));
}
echo '<h2>菜鸟教程 MysqLi_fetch_array 测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = MysqLi_fetch_array($retval, MysqLI_NUM))
{
    echo "<tr><td> {$row[0]}</td> ".
         "<td>{$row[1]} </td> ".
         "<td>{$row[2]} </td> ".
         "<td>{$row[3]} </td> ".
         "</tr>";
}
echo '</table>';
MysqLi_close($conn);
?>

使用 MysqLi_free_result 释放内存：

<?PHP
$dbhost = 'localhost:3306';  // MysqL服务器主机地址
$dbuser = 'root';            // MysqL用户名
$dbpass = '123456';          // MysqL用户名密码
$conn = MysqLi_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . MysqLi_error($conn));
}
// 设置编码，防止中文乱码
MysqLi_query($conn , "set names utf8");
 
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl';
 
MysqLi_select_db( $conn, 'RUNOOB' );
$retval = MysqLi_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . MysqLi_error($conn));
}
echo '<h2>菜鸟教程 MysqLi_fetch_array 测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = MysqLi_fetch_array($retval, MysqLI_NUM))
{
    echo "<tr><td> {$row[0]}</td> ".
         "<td>{$row[1]} </td> ".
         "<td>{$row[2]} </td> ".
         "<td>{$row[3]} </td> ".
         "</tr>";
}
echo '</table>';
// 释放内存
MysqLi_free_result($retval);
MysqLi_close($conn);
?>