PHP implements volume backup of mysql database

This article will share with you how to implement mysql database volume backup in PHP, select tables for backup, and implement single sql file and volume sql import. Friends in need can refer to the

volume export idea: count the length of sql statement variables, compare 1 character as 1 byte, if it is greater than the set volume size, write a sql file (I don’t know if this statistics is reliable. This is also a reference to other people).

The idea of ​​importing into volumes: read the sql file line by line, save each line as a complete sql statement to the array, and then loop and execute it to insert into the database. However, the create table statement is divided into multiple lines. This It needs to be dealt with separately (it took me a long time to do this);

<?php
//宋正河 转载请注明出处
set_time_limit(0);
header(&#39;content-type:text/html;charset=utf-8&#39;);
mysql_connect(&#39;localhost&#39;,&#39;root&#39;,&#39;root&#39;);
mysql_select_db(&#39;test&#39;);
$table_array=get_tables(&#39;test&#39;);
mysql_query(&#39;set names utf8&#39;);
$filesize=1024*1024*4;
$start=$_GET[&#39;start&#39;]?$_GET[&#39;start&#39;]:0;
$part=$_GET[&#39;part&#39;]?$_GET[&#39;part&#39;]:&#39;1&#39;;
$table_index=$_GET[&#39;table_index&#39;]?$_GET[&#39;table_index&#39;]:&#39;0&#39;;
$table=$table_array[$table_index];
$num=200000000;//这个数要足够大,可以是总记录数
$backupdata=&#39;&#39;;
if($start==&#39;0&#39;){
$query="SHOW CREATE TABLE `{$table}`";
$result = mysql_query($query);
$row = mysql_fetch_row($result);
$backupdata .= "DROP TABLE IF EXISTS `{$table}`;\n" . $row[1] . ";\n\n";
}
$limit=($start==&#39;0&#39;)?&#39;&#39;:" limit $start,$num ";
$query="select * from `{$table}` $limit ";
$result=mysql_query($query);
$numfields = mysql_num_fields($result); //统计字段数
while($row=mysql_fetch_row($result)){
$comma = &#39;&#39;; //存储逗号
$backupdata_tmp = "INSERT INTO `{$table}` VALUES (";
for($i=0; $i<$numfields; $i++){
$backupdata_tmp .= $comma . "&#39;" . mysql_escape_string($row[$i]) . "&#39;";
$comma = &#39;,&#39;;
}
$backupdata_tmp .= ");\n";
if(strlen($backupdata)+strlen($backupdata_tmp) > $filesize){
//写入文件并跳转
$file=&#39;data/&#39;.$table.&#39;-&#39;.$part.&#39;.sql&#39;;
file_put_contents($file,$backupdata);
echo $file.&#39; 备份完成，程序继续进行！&#39;;
$part++;
//分段
//表名
//起点
//跳转
sleep(3);
echo "<script>location.href=&#39;?start={$start}&table_index={$table_index}&part={$part}&#39;;</script>";
exit;
}
$backupdata.=$backupdata_tmp;
$start++;
}
if($backupdata){
$file=&#39;data/&#39;.$table.&#39;-&#39;.$part.&#39;.sql&#39;;
file_put_contents($file,$backupdata);
}
echo $table.&#39;备份完成！<br />&#39;;
sleep(2);
$table_index++;
if($table_array[$table_index]){
echo "<script>location.href=&#39;?table_index={$table_index}&#39;;</script>";
exit;
}else{
echo &#39;恭喜你，数据库备份完毕！&#39;;
}
function get_tables($db){
$tq = mysql_list_tables($db);
while($tr = mysql_fetch_row($tq)){
$arrtb[] = $tr[0];
}
return $arrtb;
}
?>

Summary: The above is the entire content of this article, I hope it will be helpful to everyone's study.

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