我有一个34 GB的json文件,里面有很多数据.我试图通过使用mongoimport –file file.json导入到我的mongodb中 – 但它失败了,因为文件太大而扔了一个你知道的内存系统抛出错误.是否可以使用PHP代码使用游标迭代文件？我对此没有经验,有人告诉我这是可能的.我想知道文件是如何构建的,但我不知道如何查看它的示例数组.从源代码我可以得到一个示例数组：
{
"_id": ObjectId("53b29644aafd413977b23b7e"),"summonerId": NumberLong(24570940),"region": "euw","updatedAt": NumberLong(1404212804),"season": NumberLong(4),"stats": {
"110": {
"totalSessionsPlayed": NumberLong(3),"totalSessionsLost": NumberLong(2),"totalSessionsWon": NumberLong(1),"totalChampionKills": NumberLong(34),"totalDamageDealt": NumberLong(415051),"totalDamageTaken": NumberLong(63237),"mostChampionKillsPerSession": NumberLong(12),"totalMinionKills": NumberLong(538),"totalDoubleKills": NumberLong(5),"totalTripleKills": NumberLong(1),"totalDeathsPerSession": NumberLong(18),"totalGoldEarned": NumberLong(40977),"totalTurretsKilled": NumberLong(6),"totalPhysicalDamageDealt": NumberLong(381668),"totalMagicDamageDealt": NumberLong(31340),"totalAssists": NumberLong(25),"maxChampionsKilled": NumberLong(12),"maxNumDeaths": NumberLong(10)
}
}
}
字段统计包含更多数组,110只是一个示例.
如何迭代这个大文件或如何将其导入我的mongodb？
例如;我想回应summonerid,championid(在这种情况下是110),totalSessionsPlayed.
它必须尽可能多地重新循环,直到没有为这个特殊的召唤者留下任何冠军.
再一次……召唤者ID有一个在他的职业生涯中一直在玩的冠军名单.冠军指的是(在这个例子中)110.每个召唤者都可以包含多个冠军,我希望拥有所有冠军,召唤冠军的次数(totalsessionplay).
它们有几种不同的风格：类似SAX的推送解析器和拉解析器. XML reader models: SAX versus XML pull parser概述了差异.
推分析器
这是使用salsify/json-streaming-parser的快速示例.
当它浏览文件时,我们将跟踪summonerId,championId和state.它都是基于事件的 – 您不会通过顺序解析器获得随机访问权限,因此您必须自己跟踪事物.每当totalSessionsPlayed出现时,它都会回显summonerId,championId和totalSessionsPlayed.
data.json
这是一个用于演示目的的配对json文件.
[
{
"_id": "53b29644aafd413977b23b7e","summonerId": 24570940,"stats": {
"110": {
"totalSessionsPlayed": 3,"totalSessionsLost": 2,"totalSessionsWon": 1
},"112": {
"totalSessionsPlayed": 45,"totalSessionsWon": 1
}
}
},{
"_id": "asdfasdfasdf","summonerId": 555555,"stats": {
"42": {
"totalSessionsPlayed": 65,"88": {
"totalSessionsPlayed": 99,"totalSessionsWon": 1
}
}
}
]
例：
class ListMatchUps extends JsonStreamingParser\Listener\IdleListener
{
private $key;
private $summonerId;
private $championId;
private $inStats;
public function start_document()
{
$this->key = null;
$this->summonerId = null;
$this->championId = null;
$this->inStats = false;
}
public function start_object()
{
if ($this->key === 'stats') {
$this->inStats = true;
} else if ($this->inStats) {
$this->championId = $this->key;
}
}
public function end_object()
{
if ($this->championId !== null) {
$this->championId = null;
} else if ($this->inStats) {
$this->inStats = false;
} else {
$this->summonerId = null;
}
}
public function key($key)
{
$this->key = $key;
}
public function value($value)
{
switch ($this->key) {
case 'summonerId':
$this->summonerId = $value;
break;
case 'totalSessionsPlayed':
echo "{$this->summonerId},{$this->championId},$value\n";
break;
}
}
}
$stream = fopen('data.json','r');
$listener = new ListMatchUps();
try {
$parser = new JsonStreamingParser_Parser($stream,$listener);
$parser->parse();
} catch (Exception $e) {
fclose($stream);
throw $e;
}
输出：
24570940,110,3 24570940,112,45 555555,42,65 555555,88,99
拉解析器
这是使用我最近编写的解析器,pcrov/jsonreader(需要PHP 7.)
与上面相同的data.json.
例：
use pcrov\JsonReader\JsonReader;
$reader = new JsonReader();
$reader->open("data.json");
while($reader->read("summonerId")) {
$summonerId = $reader->value();
$reader->next("stats");
foreach($reader->value() as $championId => $stats) {
echo "$summonerId,$championId,{$stats['totalSessionsPlayed']}\n";
}
}
$reader->close();
输出：
24570940,99