php - 使用 PHP 代码将 mysql 表导出为 CSV

Question

我有一个名为 pvdata 的 sql 表，我想将其导出到 csv 文件。

但是我得到了以下结果，而不是正常的表格：

 <br />
 <font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1'cellspacing='0' cellpadding='1'>
 <tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Notice: Undefined variable: header in C:\wamp\www\EXPORT TABLE\index.php on line <i>28</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0035</td><td bgcolor='#eeeeec' align='right'>256088</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='C:\wamp\www\EXPORT TABLE\index.php' bgcolor='#eeeeec'>..\index.php<b>:</b>0</td></tr>
</table></font>
"id id  state   id  state   Longitude   id  state   Longitude   Latitude    id  state   Longitude   Latitude    Altitude(km)    id  state   Longitude   Latitude    Altitude(km)    Module Tilt id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    Temperature losses coefficient  id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    Temperature losses coefficient  Nominal Operation Cell Temperature  id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    Temperature losses coefficient  Nominal Operation Cell Temperature  Invertor Effeciency id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    Temperature losses coefficient  Nominal Operation Cell Temperature  Invertor Effeciency Persil Name <br />"
<font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Notice: Undefined variable: data in C:\wamp\www\EXPORT TABLE\index.php on line <i>49</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0035</td><td bgcolor='#eeeeec' align='right'>256088</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='C:\wamp\www\EXPORT TABLE\index.php' bgcolor='#eeeeec'>..\index.php<b>:</b>0</td></tr>
</table></font>"id  state   Longitude   Latitude    Altitude(km)    Module Tilt Module Azimuth  Rated Peak Power(kW)    Temperature losses coefficient  Nominal Operation Cell Temperature  Invertor Effeciency Persil Name "
"1  ""persil""  ""0""   ""0""   ""0""   ""0""   ""0""   ""0""   ""0.0047""  ""47""  ""0.9"" ""PERSIL07"""
"2  ""other""   ""12""  ""12""  ""0""   ""15""  ""150"" ""12""  ""0.0046""  ""45""  ""0.95""    ""predefined"""

我的PHP代码是：

  <?php

$username = "root";
$password = "";
$hostname = "localhost"; 

$dbhandle = mysql_connect($hostname, $username, $password) 
  or die("Unable to connect to MySQL");

$selected = mysql_select_db("user data smart grid",$dbhandle) 
  or die("Could not select Data Base");

    header("Content-type: application/csv");
    header("Content-Disposition: attachment; filename=pvdata.csv");
    header("Pragma: no-cache");
    header("Expires: 0");



$query = "SELECT * FROM pvdata";

$export = mysql_query ($query ) or die ( "Sql error : " . mysql_error( ) );

$fields = mysql_num_fields ( $export );

for ( $i = 0; $i < $fields; $i++ )
{
    $header .= mysql_field_name( $export , $i ) . "\t";

    echo $header;
}

while( $row = mysql_fetch_row( $export ) )
{
    $line = '';
    foreach( $row as $value )
    {                                            
        if ( ( !isset( $value ) ) || ( $value == "" ) )
        {
            $value = "\t";
        }
        else
        {
            $value = str_replace( '"' , '""' , $value );
            $value = '"' . $value . '"' . "\t";
        }
        $line .= $value;
    }
    $data .= trim( $line ) . "\n";
}
$data = str_replace( "\r" , "" , $data );

if ( $data == "" )
{
    $data = "\n(0) Records Found!\n";                        
}

print "$header\n$data";

exit();

?>

那么怎么了？如果我从 phpmyadmin 手动导出表，它工作正常。如果可能，我还想获取表中列的名称。

Answer 1

在 for 循环之前将 $header 初始化为空字符串。

$header = '';//initialize header
for ( $i = 0; $i < $fields; $i++ )
{
    $header .= mysql_field_name( $export , $i ) . "\t";

    echo $header;//remove this line
}

编辑

还要在 while 循环外初始化 $data。

$data = '';
while( $row = mysql_fetch_row( $export ) )
{
    $line = '';
    foreach( $row as $value )
    {                                            
        if ( ( !isset( $value ) ) || ( $value == "" ) )
        {
            $value = "\t";
        }
        else
        {
            $value = str_replace( '"' , '""' , $value );
            $value = '"' . $value . '"' . "\t";
        }
        $line .= $value;
    }
    $data .= trim( $line ) . "\n";
}

Answer 2

我不知道这是否是错字，但在您的脚本中，

   <?php

这将导致交付一个 html 文档，并且您的标头调用将失败。因此，在“header”调用之前删除空格和任何其他输出。

您在那里收到错误消息，请尝试快速解决方案：

error_reporting(0);

第 28 行：$header 未知，这使得

$header .=

附加到未知变量。

Answer 3

您可以使用 fputcsv 函数来获得清晰的代码。

Answer 4

试试这个代码 -

<?php

    // Database Connection

    $host="localhost";
    $uname="root";
    $pass="";
    $database = "a2zwebhelp"; 

    $connection=mysql_connect($host,$uname,$pass); 

    echo mysql_error();

    //or die("Database Connection Failed");
    $selectdb=mysql_select_db($database) or 
    die("Database could not be selected"); 
    $result=mysql_select_db($database)
    or die("database cannot be selected <br>");

    // Fetch Record from Database

    $output = "";
    $table = ""; // Enter Your Table Name 
    $sql = mysql_query("select * from $table");
    $columns_total = mysql_num_fields($sql);

    // Get The Field Name

    for ($i = 0; $i < $columns_total; $i++) {
    $heading = mysql_field_name($sql, $i);
    $output .= '"'.$heading.'",';
    }
    $output .="\n";

    // Get Records from the table

    while ($row = mysql_fetch_array($sql)) {
    for ($i = 0; $i < $columns_total; $i++) {
    $output .='"'.$row["$i"].'",';
    }
    $output .="\n";
    }

    // Download the file

    $filename = time().'csv'; //For unique file name
    header('Content-type: application/csv');
    header('Content-Disposition: attachment; filename='.$filename);

    echo $output;
    exit;

    ?>

礼貌 -使用 PHP 将 MySQL 表导出到 CSV