php - 从数据库导出百万级数据(CSV文件)
时间：2021-07-01 10:21:17
帮助过：23人阅读
set_time_limit(0
);
ini_set(‘memory_limit‘, ‘128M‘
);
$fileName =
date(‘YmdHis‘,
time());
header(‘Content-Encoding: UTF-8‘
);
header("Content-type:application/vnd.ms-excel;charset=UTF-8"
);
header(‘Content-Disposition: attachment;filename="‘ .
$fileName . ‘.csv"‘
);
//打开php标准输出流
//以写入追加的方式打开
$fp =
fopen(‘php://output‘, ‘a‘
);
//连接数据库
$dbhost = ‘127.0.0.1‘
;
$dbuser = ‘root‘
;
$dbpwd = ‘‘
;
$con =
mysqli_connect(
$dbhost,
$dbuser,
$dbpwd);
if (
mysqli_connect_errno()) {
die(‘connect error‘
);
}
//选择数据库
$database = ‘test‘
;
mysqli_select_db(
$con,
$database);
//设置编码
mysqli_query(
$con, "set names UTF8"
);
//我们试着用fputcsv从数据库中导出1百万的数据
//我们每次取1万条数据，分100步来执行
//如果线上环境无法支持一次性读取1万条数据，可把$nums调小，$step相应增大。
$step = 100
;
$nums = 10000
;
$where = "";
//筛选条件
//设置标题
$title =
array(‘ID‘,‘姓名‘,‘年龄‘,‘性别‘
);
foreach($title as $key => $item) {
$title[$key] =iconv("UTF-8", "GBK", $item);
}
//将标题写到标准输出中
fputcsv($fp, $title);
for($s = 1; $s <= $step; $s++) {
$start = ($s - 1) * $nums;
$result = mysqli_query($con,"SELECT * FROM `test` ".$where." ORDER BY `id` LIMIT {$start},{$nums}");
if($result) {
while($row = mysqli_fetch_assoc($result)) {
foreach($row as $key => $item) {
//这里必须转码，不然会乱码
$row[$key] = iconv("UTF-8", "GBK", $item);
}
fputcsv($fp, $row);
}
mysqli_free_result($result); //释放结果集资源
//每1万条数据就刷新缓冲区
ob_flush();
flush();
}
}
//断开连接
mysqli_close($con);
php - 从数据库导出百万级数据(CSV文件)
标签：app 筛选条件 host sele 刷新 isp encoding flush sql
