php - 如何使用 Elastica 正确运行 _count_ 查询？

Question

我一直在使用 ElasticSearch 和 Elastica ( http://elastica.io/ ) 组合我们的搜索实现。

目前我无法弄清楚如何执行计数搜索，正如 ElasticSearch 的计数 API 中所说的那样。

谁能帮我解决这个问题？一些示例代码会很棒，因为我还不是 100% 了解所有 Elastica 对象之间的关系。

提前致谢。

Answer 1

您可以使用 Search 类 ( http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-search-type.html#count ) 与elastica ://elastica.io/api/classes/Elastica.Search.html）。

您可以在搜索类上调用 count($query, $fullResult = false) 方法以 search_type count 的形式运行查询。默认情况下，仅返回总命中数。如果 $fullResult 设置为 true，则返回包含构面的完整 ResultSet。这比运行大小设置为零的标准搜索更有效。

例如，要获取查询的命中数，您可以执行以下操作：

// Define a Query. E.g. a string query.
$elasticaQueryString = new \Elastica\Query\QueryString();

//'And' or 'Or' default : 'Or'
$elasticaQueryString->setDefaultOperator('AND');
$elasticaQueryString->setQuery('london');

// Create the actual search query object with some data.
$elasticaQuery = new \Elastica\Query();
$elasticaQuery->setQuery($elasticaQueryString);

// Setup elastica client connection to your easticsearch server (with default host and port)
$elasticaClient = new \Elastica\Client();

// Create an elastica search object
$elasticaSearch = new \Elastica\Search($elasticaClient);

// Call count method on search object to run a
$count = $elasticaSearch->count($elasticaQuery);

// output count
echo "<p>$count<p>";

一个更有用的示例可能是返回带有一些方面的完整 ResultSet 并将其限制为某个索引和类型：

// Define a Query. e.g. a string query.
$elasticaQueryString = new \Elastica\Query\QueryString();

//'And' or 'Or' default : 'Or'
$elasticaQueryString->setDefaultOperator('AND');
$elasticaQueryString->setQuery('london');

// Create some facets to be generated by query
$elasticaFacet1 = new \Elastica\Facet\Terms('myFacet1');
$elasticaFacet1->setField('colour');
$elasticaFacet1->setSize(10);

$elasticaFacet2 = new \Elastica\Facet\Terms('myFacet2');
$elasticaFacet2->setField('shape');
$elasticaFacet2->setSize(10);

// Create the actual search object with some data.
$elasticaQuery = new \Elastica\Query();

// add query string to query
$elasticaQuery->setQuery($elasticaQueryString);

//add facets to query
$elasticaQuery->addFacet($elasticaFacet1);
$elasticaQuery->addFacet($elasticaFacet2);

// Setup elastica client connection to your elasticsearch server
$elasticaClient = new \Elastica\Client(array(
    'host' => 'localhost',
    'port' => 9200
));

// If you want to restrict your search to a particular index then get that
$elasticaIndex = $elasticaClient->getIndex('myIndex');

// If you want to restrict your search to a particular type then get that
$elasticaType = $elasticaIndex->getType('myType');

// Create and elastica Search object
$elasticaSearch = new \Elastica\Search($elasticaClient);

// addIndex and addType are optional and will restrict the search to those respectivly
$countResults = $elasticaSearch->addIndex($elasticaIndex)->addType($elasticaType)->count($elasticaQuery, true);

//output total hits
echo "<p>{$countResults->getTotalHits()}</p>";

//output list of facets
echo "<ul>";
foreach ($countResults->getFacets() as $facetField => $resultTerms) {
    echo "<li><span>$facetField</span><ul>";
    foreach ($resultTerms['terms'] as $resultTerm) {
        echo "<li>{$resultTerm['term']}: {$resultTerm['count']}</li>";
    }
    echo "</ul></li>";
}
echo "</ul>";

Answer 2

使用 Elastica 2.2，您可以这样做：

public function count($index)
{
    $query = new Elastica\Query;
    $query->setSize(0);
    $results = $index->search($query);
    $count = $results->getTotalHits();

    return $count;
}