diff --git a/composer.json b/composer.json
index 487ab14..cdf424f 100644
--- a/composer.json
+++ b/composer.json
@@ -24,7 +24,8 @@
 
         "elasticsearch/elasticsearch": "^2.0",
         "ramsey/uuid": "^3.5",
-        "doctrine/dbal": "^2.5"
+        "doctrine/dbal": "^2.5",
+        "symfony/property-access": "^3.3"
     },
     "require-dev": {
         "doctrine/doctrine-bundle": "^1.6",
diff --git a/src/Component/Client/IndexInterface.php b/src/Component/Client/IndexInterface.php
index d1d7742..cef2450 100644
--- a/src/Component/Client/IndexInterface.php
+++ b/src/Component/Client/IndexInterface.php
@@ -36,4 +36,6 @@ public function search(Search $search, $type);
      * @return array
      */
     public function get($type, $id);
+
+    public function optimize();
 }
diff --git a/src/Component/Elasticsearch/ElasticsearchIndex.php b/src/Component/Elasticsearch/ElasticsearchIndex.php
index e33da99..d52fbc0 100644
--- a/src/Component/Elasticsearch/ElasticsearchIndex.php
+++ b/src/Component/Elasticsearch/ElasticsearchIndex.php
@@ -105,4 +105,12 @@ public function get($type, $id)
 
         return $response;
     }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function optimize()
+    {
+        // nothing to optimize currently.
+    }
 }
diff --git a/src/Component/Pucene/Compiler/Element/CompositeElement.php b/src/Component/Pucene/Compiler/Element/CompositeElement.php
index c4236fe..0a5a6cb 100644
--- a/src/Component/Pucene/Compiler/Element/CompositeElement.php
+++ b/src/Component/Pucene/Compiler/Element/CompositeElement.php
@@ -6,8 +6,8 @@
 
 class CompositeElement extends BaseElement
 {
-    const OR = 'or';
-    const AND = 'and';
+    const OPERATOR_OR = 'or';
+    const OPERATOR_AND = 'and';
 
     /**
      * @var string
diff --git a/src/Component/Pucene/Compiler/Visitor/Compound/BoolVisitor.php b/src/Component/Pucene/Compiler/Visitor/Compound/BoolVisitor.php
index e8f9412..6b9e5d5 100644
--- a/src/Component/Pucene/Compiler/Visitor/Compound/BoolVisitor.php
+++ b/src/Component/Pucene/Compiler/Visitor/Compound/BoolVisitor.php
@@ -45,11 +45,11 @@ public function visit(QueryInterface $query, StorageInterface $storage)
         }
 
         if (count($andElements) === 0) {
-            return new CompositeElement(CompositeElement:: OR, $shouldElements);
+            return new CompositeElement(CompositeElement::OPERATOR_OR, $shouldElements);
         }
 
         return new BoolElement(
-            new CompositeElement(CompositeElement:: AND, $andElements),
+            new CompositeElement(CompositeElement::OPERATOR_AND, $andElements),
             array_merge($mustElements, $shouldElements)
         );
     }
diff --git a/src/Component/Pucene/Compiler/Visitor/FullText/MatchVisitor.php b/src/Component/Pucene/Compiler/Visitor/FullText/MatchVisitor.php
index 9052235..4945591 100644
--- a/src/Component/Pucene/Compiler/Visitor/FullText/MatchVisitor.php
+++ b/src/Component/Pucene/Compiler/Visitor/FullText/MatchVisitor.php
@@ -39,6 +39,6 @@ public function visit(QueryInterface $query, StorageInterface $storage)
             $terms[] = new TermElement($query->getField(), $token->getEncodedTerm());
         }
 
-        return new CompositeElement(CompositeElement:: OR, $terms);
+        return new CompositeElement(CompositeElement:: OPERATOR_OR, $terms);
     }
 }
diff --git a/src/Component/Pucene/Compiler/Visitor/Specialized/MoreLikeThisVisitor.php b/src/Component/Pucene/Compiler/Visitor/Specialized/MoreLikeThisVisitor.php
index d5a9259..81dbde5 100644
--- a/src/Component/Pucene/Compiler/Visitor/Specialized/MoreLikeThisVisitor.php
+++ b/src/Component/Pucene/Compiler/Visitor/Specialized/MoreLikeThisVisitor.php
@@ -62,15 +62,15 @@ public function visit(QueryInterface $query, StorageInterface $storage)
 
         $mustNotElements = $this->getMustNotElements($query->getLike());
         if (0 === count($mustNotElements)) {
-            return new CompositeElement(CompositeElement:: OR, $elements);
+            return new CompositeElement(CompositeElement:: OPERATOR_OR, $elements);
         }
 
         return new BoolElement(
             new CompositeElement(
-                CompositeElement:: AND,
+                CompositeElement:: OPERATOR_AND,
                 [
-                    new CompositeElement(CompositeElement:: AND, $mustNotElements),
-                    new CompositeElement(CompositeElement:: OR, $elements),
+                    new CompositeElement(CompositeElement:: OPERATOR_AND, $mustNotElements),
+                    new CompositeElement(CompositeElement:: OPERATOR_OR, $elements),
                 ]
             ),
             $elements
diff --git a/src/Component/Pucene/Compiler/Visitor/TermLevel/IdsVisitor.php b/src/Component/Pucene/Compiler/Visitor/TermLevel/IdsVisitor.php
index cc9944f..9cbb9c1 100644
--- a/src/Component/Pucene/Compiler/Visitor/TermLevel/IdsVisitor.php
+++ b/src/Component/Pucene/Compiler/Visitor/TermLevel/IdsVisitor.php
@@ -24,6 +24,6 @@ public function visit(QueryInterface $query, StorageInterface $storage)
             return $ids;
         }
 
-        return new CompositeElement(CompositeElement:: AND, [$ids, new TypeElement($query->getType())]);
+        return new CompositeElement(CompositeElement:: OPERATOR_AND, [$ids, new TypeElement($query->getType())]);
     }
 }
diff --git a/src/Component/Pucene/Dbal/DbalStorage.php b/src/Component/Pucene/Dbal/DbalStorage.php
index 39cd051..ed6deb5 100644
--- a/src/Component/Pucene/Dbal/DbalStorage.php
+++ b/src/Component/Pucene/Dbal/DbalStorage.php
@@ -144,6 +144,11 @@ public function termStatistics()
         return new DbalTermStatistics($this->connection, $this->getSchema());
     }
 
+    public function optimize()
+    {
+        $this->persister->optimize();
+    }
+
     public function getConnection()
     {
         return $this->connection;
diff --git a/src/Component/Pucene/Dbal/DocumentPersister.php b/src/Component/Pucene/Dbal/DocumentPersister.php
index a54e9b3..5bd07db 100644
--- a/src/Component/Pucene/Dbal/DocumentPersister.php
+++ b/src/Component/Pucene/Dbal/DocumentPersister.php
@@ -12,12 +12,12 @@ class DocumentPersister
     /**
      * @var Connection
      */
-    private $connection;
+    public $connection;
 
     /**
      * @var PuceneSchema
      */
-    private $schema;
+    public $schema;
 
     /**
      * @param Connection $connection
@@ -56,21 +56,51 @@ public function persist(Document $document, array $fields)
                     $token->getEncodedTerm(),
                     ElasticsearchPrecision::fieldNorm($field->getNumberOfTerms())
                 );
+
+                $this->connection->createQueryBuilder()
+                    ->update($this->schema->getDocumentTermsTableName())
+                    ->set('frequency', 'frequency + 1')
+                    ->andWhere('field_name = :fieldName')
+                    ->andWhere('term = :term')
+                    ->setParameter('fieldName', $field->getName())
+                    ->setParameter('term', $token->getEncodedTerm())
+                    ->execute();
             }
 
             // update term frequency
             foreach ($fieldTerms as $term => $frequency) {
-                $this->connection->update(
-                    $this->schema->getDocumentTermsTableName(),
-                    [
-                        'term_frequency' => $frequency,
-                    ],
-                    ['document_id' => $document->getId(), 'field_name' => $field->getName(), 'term' => $term]
-                );
+                $this->connection->createQueryBuilder()
+                    ->update($this->schema->getDocumentTermsTableName())
+                    ->set('term_frequency', sqrt($frequency))
+                    ->set('score', 'field_norm * ' . sqrt($frequency))
+                    ->andWhere('document_ID = :document')
+                    ->andWhere('field_name = :fieldName')
+                    ->andWhere('term = :term')
+                    ->setParameter('document', $document->getId())
+                    ->setParameter('fieldName', $field->getName())
+                    ->setParameter('term', $term)
+                    ->execute();
             }
         }
     }
 
+    public function optimize()
+    {
+        // TODO recalculate term frequency
+
+        $docCount = $this->connection->createQueryBuilder()
+            ->select('COUNT(id)')
+            ->from($this->schema->getDocumentsTableName())
+            ->execute()
+            ->fetchColumn();
+
+        // calculate inverse-document-frequency
+        $this->connection->createQueryBuilder()
+            ->update($this->schema->getDocumentTermsTableName())
+            ->set('idf', '1 + log(' . $docCount . ' / (frequency + 1))')
+            ->execute();
+    }
+
     /**
      * @param Document $document
      */
@@ -101,6 +131,16 @@ protected function insertDocument(Document $document)
      */
     protected function insertToken(string $documentId, string $fieldName, $term, $fieldNorm)
     {
+        $frequency = $this->connection->createQueryBuilder()
+            ->select('frequency')
+            ->from($this->schema->getDocumentTermsTableName())
+            ->andWhere('field_name = :fieldName')
+            ->andWhere('term = :term')
+            ->setParameter('fieldName', $fieldName)
+            ->setParameter('term', $term)
+            ->execute()
+            ->fetchColumn();
+
         $this->connection->insert(
             $this->schema->getDocumentTermsTableName(),
             [
@@ -108,6 +148,7 @@ protected function insertToken(string $documentId, string $fieldName, $term, $fi
                 'field_name' => $fieldName,
                 'term' => $term,
                 'field_norm' => $fieldNorm,
+                'frequency' => $frequency ?: 0,
             ]
         );
     }
diff --git a/src/Component/Pucene/Dbal/Interpreter/DbalInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/DbalInterpreter.php
index 5afcb6f..b6ef451 100644
--- a/src/Component/Pucene/Dbal/Interpreter/DbalInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/DbalInterpreter.php
@@ -8,10 +8,17 @@
 use Pucene\Component\Pucene\Model\Document;
 use Pucene\Component\QueryBuilder\Search;
 use Pucene\Component\QueryBuilder\Sort\IdSort;
+use Pucene\Component\QueryBuilder\Sort\ScoreSort;
 use Pucene\Component\Symfony\Pool\PoolInterface;
+use Pucene\Component\Utils\SortUtils;
 
 class DbalInterpreter
 {
+    public static $sortPaths = [
+        ScoreSort::class => 'score',
+        IdSort::class => 'id',
+    ];
+
     /**
      * @var PoolInterface
      */
@@ -42,8 +49,6 @@ public function interpret(array $types, Search $search, DbalStorage $storage, El
             ->select('document.*')
             ->from($schema->getDocumentsTableName(), 'document')
             ->where('document.type IN (?)')
-            ->setMaxResults($search->getSize())
-            ->setFirstResult($search->getFrom())
             ->setParameter(0, implode(',', $types));
 
         /** @var InterpreterInterface $interpreter */
@@ -54,21 +59,6 @@ public function interpret(array $types, Search $search, DbalStorage $storage, El
         }
 
         $scoringAlgorithm = new ScoringAlgorithm($queryBuilder, $schema, $this->interpreterPool);
-        $expression = $interpreter->scoring($element, $scoringAlgorithm);
-
-        if ($expression) {
-            $queryBuilder->addSelect('(' . $expression . ') as score')->orderBy('score', 'desc');
-        } else {
-            $queryBuilder->addSelect('1 as score');
-        }
-
-        if (0 < count($search->getSorts())) {
-            foreach ($search->getSorts() as $sort) {
-                if ($sort instanceof IdSort) {
-                    $queryBuilder->addOrderBy('id', $sort->getOrder());
-                }
-            }
-        }
 
         $result = [];
         foreach ($queryBuilder->execute()->fetchAll() as $row) {
@@ -77,10 +67,17 @@ public function interpret(array $types, Search $search, DbalStorage $storage, El
                 $row['type'],
                 $storage->getName(),
                 json_decode($row['document'], true),
-                array_key_exists('score', $row) ? (float) $row['score'] : 1
+                $interpreter->newScoring($element, $scoringAlgorithm, $row)
             );
         }
 
-        return $result;
+        $paths = [];
+        foreach ($search->getSorts() as $sort) {
+            $paths[] = self::$sortPaths[get_class($sort)];
+        }
+
+        $result = SortUtils::multisort($result, $paths);
+
+        return array_splice($result, $search->getFrom(), $search->getSize());
     }
 }
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/BoolInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/BoolInterpreter.php
index dc9a5bf..0945e0a 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/BoolInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/BoolInterpreter.php
@@ -35,6 +35,10 @@ public function __construct(PoolInterface $interpreterPool)
      */
     public function interpret(ElementInterface $element, PuceneQueryBuilder $queryBuilder)
     {
+        foreach ($element->getScoringElements() as $innerElement) {
+            $this->getInterpreter($innerElement)->interpret($innerElement, $queryBuilder);
+        }
+
         return $this->getInterpreter($element->getElement())->interpret($element->getElement(), $queryBuilder);
     }
 
@@ -74,6 +78,42 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
         );
     }
 
+    /**
+     * {@inheritdoc}
+     *
+     * @param BoolElement $element
+     */
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        if (count($element->getScoringElements()) === 0 || $element->getBoost() === 0) {
+            return 0;
+        } elseif (count($element->getScoringElements()) === 1) {
+            $innerElement = $element->getScoringElements()[0];
+            $interpreter = $this->interpreterPool->get(get_class($innerElement));
+
+            return $interpreter->newScoring($innerElement, $scoring, $row);
+        }
+
+        if (!$queryNorm) {
+            $queryNorm = $scoring->queryNorm($this->getTerms($element->getScoringElements()));
+        }
+
+        $score = 0;
+        $coord = 0;
+        foreach ($element->getScoringElements() as $innerElement) {
+            /** @var InterpreterInterface $interpreter */
+            $interpreter = $this->interpreterPool->get(get_class($innerElement));
+
+            $score += $interpreter->newScoring($innerElement, $scoring, $row, $queryNorm);
+
+            if ($interpreter->matches($innerElement, $row)) {
+                $coord += 1 / count($element->getScoringElements());
+            }
+        }
+
+        return $score * $coord * $element->getBoost();
+    }
+
     private function getTerms(array $elements)
     {
         $terms = [];
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/CompositeInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/CompositeInterpreter.php
index 44245f0..34697f5 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/CompositeInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/CompositeInterpreter.php
@@ -29,7 +29,7 @@ public function interpret(ElementInterface $element, PuceneQueryBuilder $queryBu
         $expr = $queryBuilder->expr();
 
         $expression = $expr->orX();
-        if ($element->getOperator() === CompositeElement:: AND) {
+        if ($element->getOperator() === CompositeElement:: OPERATOR_AND) {
             $expression = $expr->andX();
         }
 
@@ -53,4 +53,35 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
     {
         return parent::scoring(new BoolElement($element, $element->getElements()), $scoring, $queryNorm);
     }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @param CompositeElement $element
+     */
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        return parent::newScoring(new BoolElement($element, $element->getElements()), $scoring, $row, $queryNorm);
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @param CompositeElement $element
+     */
+    public function matches(ElementInterface $element, array $row)
+    {
+        foreach ($element->getElements() as $innerElement) {
+            $interpreter = $this->interpreterPool->get(get_class($innerElement));
+            if ($interpreter->matches($innerElement, $row)) {
+                if ($element->getOperator() === CompositeElement::OPERATOR_OR) {
+                    return true;
+                }
+            } elseif ($element->getOperator() === CompositeElement::OPERATOR_AND) {
+                return false;
+            }
+        }
+
+        return $element->getOperator() === CompositeElement::OPERATOR_AND;
+    }
 }
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/IdsInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/IdsInterpreter.php
index a63db91..839885a 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/IdsInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/IdsInterpreter.php
@@ -38,4 +38,14 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
     {
         return (new MathExpressionBuilder())->value(1);
     }
+
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        return 1;
+    }
+
+    public function matches(ElementInterface $element, array $row)
+    {
+        return in_array($row['id'], $element->getIds());
+    }
 }
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/MatchAllInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/MatchAllInterpreter.php
index ba5b621..c340875 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/MatchAllInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/MatchAllInterpreter.php
@@ -30,4 +30,9 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
     {
         return (new MathExpressionBuilder())->value(1);
     }
+
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        return 1;
+    }
 }
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/NotInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/NotInterpreter.php
index 78edb52..70ed3d2 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/NotInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/NotInterpreter.php
@@ -53,6 +53,13 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
         );
     }
 
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        $interpreter = $this->getInterpreter($element->getElement());
+
+        return $element->getBoost() * $interpreter->newScoring($element, $scoring, $row, $queryNorm);
+    }
+
     /**
      * Returns interpreter for element.
      *
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/TermInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/TermInterpreter.php
index 5ea3c3d..a18958c 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/TermInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/TermInterpreter.php
@@ -18,10 +18,12 @@ class TermInterpreter implements InterpreterInterface
     public function interpret(ElementInterface $element, PuceneQueryBuilder $queryBuilder)
     {
         $expr = $queryBuilder->expr();
+        $name = $queryBuilder->joinTerm($element->getField(), $element->getTerm());
 
-        return $expr->isNotNull(
-            $queryBuilder->joinTerm($element->getField(), $element->getTerm()) . '.id'
-        );
+        $queryBuilder->addSelect(sprintf('(%1$s.score) as %1$sValue', $name));
+        $queryBuilder->addSelect(sprintf('%1$s.idf as %1$sIdf', $name));
+
+        return $expr->isNotNull($name . '.id');
     }
 
     /**
@@ -33,4 +35,43 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
     {
         return $scoring->scoreTerm($element, $queryNorm, $element->getBoost());
     }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @param TermElement $element
+     */
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        $termName = 'term' . ucfirst($element->getField()) . ucfirst($element->getTerm());
+        $idfName = $termName . 'Idf';
+        $valueName = $termName . 'Value';
+        if (!array_key_exists($valueName, $row)
+            || !array_key_exists($idfName, $row)
+            || $row[$valueName] === null
+            || $row[$idfName] === null
+        ) {
+            return 0;
+        }
+
+        $idf = $row[$idfName];
+        $factor = $idf * $element->getBoost();
+        if ($queryNorm) {
+            $factor *= $idf * $queryNorm;
+        }
+
+        return $row[$valueName] * $factor;
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @param TermElement $element
+     */
+    public function matches(ElementInterface $element, array $row)
+    {
+        $termName = 'term' . ucfirst($element->getField()) . ucfirst($element->getTerm()) . 'Value';
+
+        return array_key_exists($termName, $row) && $row[$termName] !== null;
+    }
 }
diff --git a/src/Component/Pucene/Dbal/Interpreter/Element/TypeInterpreter.php b/src/Component/Pucene/Dbal/Interpreter/Element/TypeInterpreter.php
index d70301d..06fb524 100644
--- a/src/Component/Pucene/Dbal/Interpreter/Element/TypeInterpreter.php
+++ b/src/Component/Pucene/Dbal/Interpreter/Element/TypeInterpreter.php
@@ -30,4 +30,14 @@ public function scoring(ElementInterface $element, ScoringAlgorithm $scoring, $q
     {
         return (new MathExpressionBuilder())->value(1);
     }
+
+    public function newScoring(ElementInterface $element, ScoringAlgorithm $scoring, array $row, $queryNorm = null)
+    {
+        return 1;
+    }
+
+    public function matches(ElementInterface $element, array $row)
+    {
+        return $row['id'] === $element->getType();
+    }
 }
diff --git a/src/Component/Pucene/Dbal/PuceneSchema.php b/src/Component/Pucene/Dbal/PuceneSchema.php
index f4a21cb..d1fbd23 100644
--- a/src/Component/Pucene/Dbal/PuceneSchema.php
+++ b/src/Component/Pucene/Dbal/PuceneSchema.php
@@ -58,8 +58,11 @@ private function createDocumentTermsTable()
         $fields->addColumn('document_id', 'string', ['length' => 255]);
         $fields->addColumn('field_name', 'string', ['length' => 255]);
         $fields->addColumn('term', 'string', ['length' => 255]);
-        $fields->addColumn('term_frequency', 'integer', ['default' => 0]);
+        $fields->addColumn('term_frequency', 'float', ['default' => 0]);
         $fields->addColumn('field_norm', 'float', ['default' => 0]);
+        $fields->addColumn('score', 'float', ['default' => 0]);
+        $fields->addColumn('frequency', 'integer', ['default' => 0]);
+        $fields->addColumn('idf', 'float', ['default' => 0]);
 
         $fields->setPrimaryKey(['id']);
         $fields->addForeignKeyConstraint(
diff --git a/src/Component/Pucene/Dbal/ScoringAlgorithm.php b/src/Component/Pucene/Dbal/ScoringAlgorithm.php
index 77cb22f..8a5e3b2 100644
--- a/src/Component/Pucene/Dbal/ScoringAlgorithm.php
+++ b/src/Component/Pucene/Dbal/ScoringAlgorithm.php
@@ -38,6 +38,11 @@ class ScoringAlgorithm
      */
     private $docCount;
 
+    /**
+     * @var int[]
+     */
+    private $docCounts = [];
+
     /**
      * @param PuceneQueryBuilder $queryBuilder
      * @param PuceneSchema $schema
@@ -98,7 +103,7 @@ public function getConnection(): Connection
         return $this->queryBuilder->getConnection();
     }
 
-    private function inverseDocumentFrequency(ElementInterface $element): float
+    public function inverseDocumentFrequency(ElementInterface $element): float
     {
         return $this->calculateInverseDocumentFrequency($this->getDocCountForElement($element));
     }
@@ -108,13 +113,18 @@ private function inverseDocumentFrequency(ElementInterface $element): float
      *
      * @return float
      */
-    private function calculateInverseDocumentFrequency($docCount)
+    public function calculateInverseDocumentFrequency($docCount)
     {
         return 1 + log((float) $this->getDocCount() / ($docCount + 1));
     }
 
     private function getDocCountForElement(ElementInterface $element)
     {
+        $key = $element->getField() . $element->getTerm();
+        if (array_key_exists($key, $this->docCounts)) {
+            return $this->docCounts[$key];
+        }
+
         $queryBuilder = (new PuceneQueryBuilder($this->queryBuilder->getConnection(), $this->schema))
             ->select('count(document.id) as count')
             ->from($this->schema->getDocumentsTableName(), 'document');
@@ -124,10 +134,10 @@ private function getDocCountForElement(ElementInterface $element)
             $queryBuilder->where($expression);
         }
 
-        return (int) $queryBuilder->execute()->fetchColumn();
+        return $this->docCounts[$key] = (int)$queryBuilder->execute()->fetchColumn();
     }
 
-    private function getDocCount()
+    public function getDocCount()
     {
         if ($this->docCount) {
             return $this->docCount;
diff --git a/src/Component/Pucene/PuceneIndex.php b/src/Component/Pucene/PuceneIndex.php
index bde92c8..c61715e 100644
--- a/src/Component/Pucene/PuceneIndex.php
+++ b/src/Component/Pucene/PuceneIndex.php
@@ -96,4 +96,9 @@ public function get($type, $id)
     {
         return $this->storage->get($type, $id);
     }
+
+    public function optimize()
+    {
+        $this->storage->optimize();
+    }
 }
diff --git a/src/Component/Pucene/StorageInterface.php b/src/Component/Pucene/StorageInterface.php
index bda636d..f890224 100644
--- a/src/Component/Pucene/StorageInterface.php
+++ b/src/Component/Pucene/StorageInterface.php
@@ -20,4 +20,6 @@ public function search(Search $search, $type);
     public function get($type, $id);
 
     public function termStatistics();
+
+    public function optimize();
 }
diff --git a/src/Component/QueryBuilder/Search.php b/src/Component/QueryBuilder/Search.php
index d55e695..98ee04d 100644
--- a/src/Component/QueryBuilder/Search.php
+++ b/src/Component/QueryBuilder/Search.php
@@ -3,6 +3,7 @@
 namespace Pucene\Component\QueryBuilder;
 
 use Pucene\Component\QueryBuilder\Query\QueryInterface;
+use Pucene\Component\QueryBuilder\Sort\ScoreSort;
 use Pucene\Component\QueryBuilder\Sort\SortInterface;
 
 class Search
@@ -39,6 +40,8 @@ class Search
     public function __construct(QueryInterface $query = null)
     {
         $this->query = $query;
+
+        $this->sorts = [new ScoreSort()];
     }
 
     /**
diff --git a/src/Component/QueryBuilder/Sort/ScoreSort.php b/src/Component/QueryBuilder/Sort/ScoreSort.php
new file mode 100644
index 0000000..a266665
--- /dev/null
+++ b/src/Component/QueryBuilder/Sort/ScoreSort.php
@@ -0,0 +1,27 @@
+<?php
+
+namespace Pucene\Component\QueryBuilder\Sort;
+
+class ScoreSort implements SortInterface
+{
+    /**
+     * @var string
+     */
+    private $order;
+
+    /**
+     * @param string $order
+     */
+    public function __construct(string $order = self::ASC)
+    {
+        $this->order = $order;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getOrder(): string
+    {
+        return $this->order;
+    }
+}
diff --git a/src/Component/Utils/SortUtils.php b/src/Component/Utils/SortUtils.php
new file mode 100644
index 0000000..44e9946
--- /dev/null
+++ b/src/Component/Utils/SortUtils.php
@@ -0,0 +1,102 @@
+<?php
+
+/*
+ * This file is part of Sulu.
+ *
+ * (c) MASSIVE ART WebServices GmbH
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace Pucene\Component\Utils;
+
+use Symfony\Component\PropertyAccess\PropertyAccess;
+
+/**
+ * Sorting utilities.
+ */
+final class SortUtils
+{
+    /**
+     * Cannot instantiate this class.
+     */
+    final private function __construct()
+    {
+    }
+
+    /**
+     * Sort the given array of arrays/objects using paths.
+     *
+     * e.g.
+     *
+     *      $data = array(
+     *          array('foobar' => 'b'),
+     *          array('foobar' => 'a'),
+     *      );
+     *
+     *      SortUtils::multisort($data, '[foobar]', 'asc');
+     *
+     *      echo $data[0]; // "a"
+     *
+     * You can also use method names:
+     *
+     *      SortUtils::multisort($data, 'getFoobar', 'asc');
+     *
+     * Or sort on multidimensional arrays:
+     *
+     *      SortUtils::multisort($data, 'foobar.bar.getFoobar', 'asc');
+     *
+     * And you can sort on multiple paths:
+     *
+     *      SortUtils::multisort($data, array('foo', 'bar'), 'asc');
+     *
+     * The path is any path accepted by the property access component:
+     *
+     * @see http://symfony.com/doc/current/components/property_access/introduction.html
+     *
+     * @param array $values
+     * @param string|array $paths Path or paths on which to sort on
+     * @param string $direction Direction to sort in (either ASC or DESC)
+     *
+     * @return array
+     */
+    public static function multisort($values, $paths, $direction = 'ASC')
+    {
+        $accessor = PropertyAccess::createPropertyAccessor();
+
+        $values = (array) $values;
+        $paths = (array) $paths;
+
+        usort(
+            $values,
+            function ($a, $b) use ($accessor, $paths) {
+                foreach ($paths as $i => $path) {
+                    $aOrder = $accessor->getValue($a, $path);
+                    $bOrder = $accessor->getValue($b, $path);
+
+                    if (is_string($aOrder)) {
+                        $aOrder = strtolower($aOrder);
+                        $bOrder = strtolower($bOrder);
+                    }
+
+                    if ($aOrder == $bOrder) {
+                        if (count($paths) == ($i + 1)) {
+                            return 0;
+                        } else {
+                            continue;
+                        }
+                    }
+
+                    return ($aOrder < $bOrder) ? -1 : 1;
+                }
+            }
+        );
+
+        if (strtoupper($direction) == 'DESC') {
+            $values = array_reverse($values);
+        }
+
+        return $values;
+    }
+}
diff --git a/tests/src/TestBundle/Command/ImportJsonCommand.php b/tests/src/TestBundle/Command/ImportJsonCommand.php
index 4fee19f..2f566c7 100644
--- a/tests/src/TestBundle/Command/ImportJsonCommand.php
+++ b/tests/src/TestBundle/Command/ImportJsonCommand.php
@@ -2,6 +2,7 @@
 
 namespace Pucene\Tests\TestBundle\Command;
 
+use Pucene\Component\Client\ClientInterface;
 use Symfony\Bundle\FrameworkBundle\Command\ContainerAwareCommand;
 use Symfony\Component\Console\Helper\ProgressBar;
 use Symfony\Component\Console\Input\InputArgument;
@@ -30,6 +31,7 @@ protected function configure()
      */
     protected function execute(InputInterface $input, OutputInterface $output)
     {
+        /** @var ClientInterface $client */
         $client = $this->getContainer()->get('pucene.' . $input->getOption('adapter') . '.client');
         $index = $client->get($input->getArgument('index'));
 
@@ -44,6 +46,8 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $progressBar->advance();
         }
 
+        $index->optimize();
+
         $progressBar->finish();
     }
 }
diff --git a/tests/src/TestBundle/Command/ImportWikidataCommand.php b/tests/src/TestBundle/Command/ImportWikidataCommand.php
index d8612f0..6d51301 100644
--- a/tests/src/TestBundle/Command/ImportWikidataCommand.php
+++ b/tests/src/TestBundle/Command/ImportWikidataCommand.php
@@ -58,6 +58,8 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $progressBar->advance();
         }
 
+        $index->optimize();
+
         $progressBar->finish();
     }
 }