He encontrado en fluidbyte una sencilla función para hacer backup de una base de datos MySQL.
function backupDatabase($file){
$tables = array();
$result = mysql_query('SHOW TABLES');
while($row = mysql_fetch_row($result)){ $tables[] = $row[0]; }
//cycle through
$return = "";
foreach($tables as $table){
$result = mysql_query('SELECT * FROM '.$table);
$num_fields = mysql_num_fields($result);
$return.= 'DROP TABLE '.$table.';';
$row2 = mysql_fetch_row(mysql_query('SHOW CREATE TABLE '.$table));
$return.= "nn".$row2[1].";nn";
for ($i = 0; $i < $num_fields; $i++){
while($row = mysql_fetch_row($result)){
$return.= 'INSERT INTO '.$table.' VALUES(';
for($j=0; $j<$num_fields; $j++){
$row[$j] = addslashes($row[$j]);
$row[$j] = ereg_replace("n","\n",$row[$j]);
if (isset($row[$j])) { $return.= '"'.$row[$j].'"' ; } else { $return.= '""'; }
if ($j<($num_fields-1)) { $return.= ','; }
}
$return.= ");n";
}
}
$return.="nnn";
}
//save file
$handle = fopen($file,'w+');
fwrite($handle,$return);
fclose($handle);
}
Su uso es bien sencillo:
backupDatabase('/path_to_file/backup' . date('m-d-y') . '.sql');
