使用PHP / PDO将大型MySQL表导出为CSV

Question

I am currently using arrays and fputcsv to export MySQL tables to a csv file. This works great, however I have one table which is too large (100,000 + rows) for this method and so my site times out.

My current code is;

<?php                                    
//open database connection                            
require ('../database-config.php');
header('Content-Type: text/csv');
header('Content-Disposition: attachment;filename=exported_archive_all.csv');

//SQL Query for Data
$sql = "SELECT * FROM inverter_data_archive;";        
//Prepare Query, Bind Parameters, Excute Query
$STH = $dbh->prepare($sql);
$STH->execute();

//Export to .CSV
$fp = fopen('php://output', 'w');

// first set
$first_row = $STH->fetch(PDO::FETCH_ASSOC);
$headers = array_keys($first_row);
fputcsv($fp, $headers); // put the headers
fputcsv($fp, array_values($first_row)); // put the first row

while ($row = $STH->fetch(PDO::FETCH_NUM))  {
fputcsv($fp,$row); // push the rest
}
fclose($fp);        
?>

I have read that a possible approach is to read each data row individually from the query result set and write directly to php://output, then read the next row, etc; rather than building a large array or building the csv in memory.

I've tried a few things but I struggle with for loops so any help on how to achieve this would be much appreciated.

Answer 1

检查您的php.ini文件查找搜索最大值和折痕值，例如max_execution_time max_input_time max_input_vars max_input_vars post_max_size upload_max_filesize