diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index 82c1408683..3115ceea47 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -248,7 +248,10 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 			$query->andWhere($query->expr()->neq('uri', $query->createNamedParameter(BirthdayService::BIRTHDAY_CALENDAR_URI)));
 		}
 
-		return (int)$query->execute()->fetchColumn();
+		$result = $query->execute();
+		$column = (int)$result->fetchColumn();
+		$result->closeCursor();
+		return $column;
 	}
 
 	/**
@@ -2346,7 +2349,9 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 		$query->select('synctoken')
 			->from($table)
 			->where($query->expr()->eq('id', $query->createNamedParameter($calendarId)));
-		$syncToken = (int)$query->execute()->fetchColumn();
+		$result = $query->execute();
+		$syncToken = (int)$result->fetchColumn();
+		$result->closeCursor();
 
 		$query = $this->db->getQueryBuilder();
 		$query->insert('calendarchanges')
diff --git a/apps/dav/lib/CardDAV/CardDavBackend.php b/apps/dav/lib/CardDAV/CardDavBackend.php
index 14ade3f16e..d517e212c3 100644
--- a/apps/dav/lib/CardDAV/CardDavBackend.php
+++ b/apps/dav/lib/CardDAV/CardDavBackend.php
@@ -138,7 +138,10 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 			->from('addressbooks')
 			->where($query->expr()->eq('principaluri', $query->createNamedParameter($principalUri)));
 
-		return (int)$query->execute()->fetchColumn();
+		$result = $query->execute();
+		$column = (int) $result->fetchColumn();
+		$result->closeCursor();
+		return $column;
 	}
 
 	/**
diff --git a/apps/dav/lib/Migration/BuildCalendarSearchIndex.php b/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
index d16873fee2..117cef7d7b 100644
--- a/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
+++ b/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
@@ -75,7 +75,9 @@ class BuildCalendarSearchIndex implements IRepairStep {
 		$query = $this->db->getQueryBuilder();
 		$query->select($query->createFunction('MAX(' . $query->getColumnName('id') . ')'))
 			->from('calendarobjects');
-		$maxId = (int)$query->execute()->fetchColumn();
+		$result = $query->execute();
+		$maxId = (int) $result->fetchColumn();
+		$result->closeCursor();
 
 		$output->info('Add background job');
 		$this->jobList->add(BuildCalendarSearchIndexBackgroundJob::class, [
diff --git a/apps/dav/lib/Migration/RegisterBuildReminderIndexBackgroundJob.php b/apps/dav/lib/Migration/RegisterBuildReminderIndexBackgroundJob.php
index 2aef1617df..58e798f42c 100644
--- a/apps/dav/lib/Migration/RegisterBuildReminderIndexBackgroundJob.php
+++ b/apps/dav/lib/Migration/RegisterBuildReminderIndexBackgroundJob.php
@@ -86,7 +86,9 @@ class RegisterBuildReminderIndexBackgroundJob implements IRepairStep {
 		$query = $this->db->getQueryBuilder();
 		$query->select($query->createFunction('MAX(' . $query->getColumnName('id') . ')'))
 			->from('calendarobjects');
-		$maxId = (int)$query->execute()->fetchColumn();
+		$result = $query->execute();
+		$maxId = (int) $result->fetchColumn();
+		$result->closeCursor();
 
 		$output->info('Add background job');
 		$this->jobList->add(BuildReminderIndexBackgroundJob::class, [
diff --git a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
index 95617001b3..abcec14fb7 100644
--- a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
+++ b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
@@ -549,7 +549,12 @@ class CardDavBackendTest extends TestCase {
 		$this->invokePrivate($backend, 'updateProperties', [$bookId, $cardUri, $vCard->serialize()]);
 
 		$query = $this->db->getQueryBuilder();
-		$result = $query->select('*')->from('cards_properties')->execute()->fetchAll();
+		$query->select('*')
+			->from('cards_properties');
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		$this->assertSame(2, count($result));
 
@@ -569,7 +574,12 @@ class CardDavBackendTest extends TestCase {
 		$this->invokePrivate($backend, 'updateProperties', [$bookId, $cardUri, $vCard->serialize()]);
 
 		$query = $this->db->getQueryBuilder();
-		$result = $query->select('*')->from('cards_properties')->execute()->fetchAll();
+		$query->select('*')
+			->from('cards_properties');
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		$this->assertSame(1, count($result));
 
@@ -609,7 +619,13 @@ class CardDavBackendTest extends TestCase {
 		$this->invokePrivate($this->backend, 'purgeProperties', [1, 1]);
 
 		$query = $this->db->getQueryBuilder();
-		$result = $query->select('*')->from('cards_properties')->execute()->fetchAll();
+		$query->select('*')
+			->from('cards_properties');
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
+
 		$this->assertSame(1, count($result));
 		$this->assertSame(1 ,(int)$result[0]['addressbookid']);
 		$this->assertSame(2 ,(int)$result[0]['cardid']);
diff --git a/apps/dav/tests/unit/DAV/CustomPropertiesBackendTest.php b/apps/dav/tests/unit/DAV/CustomPropertiesBackendTest.php
index 3e22193fcb..2633ccf544 100644
--- a/apps/dav/tests/unit/DAV/CustomPropertiesBackendTest.php
+++ b/apps/dav/tests/unit/DAV/CustomPropertiesBackendTest.php
@@ -109,7 +109,12 @@ class CustomPropertiesBackendTest extends TestCase {
 			->from('properties')
 			->where($query->expr()->eq('userid', $query->createNamedParameter($user)))
 			->where($query->expr()->eq('propertypath', $query->createNamedParameter($this->formatPath($path))));
-		return $query->execute()->fetchAll(\PDO::FETCH_KEY_PAIR);
+
+
+		$result = $query->execute();
+		$data = $result->fetchAll(\PDO::FETCH_KEY_PAIR);
+		$result->closeCursor();
+		return $data;
 	}
 
 	public function testPropFindNoDbCalls() {
diff --git a/apps/federatedfilesharing/lib/FederatedShareProvider.php b/apps/federatedfilesharing/lib/FederatedShareProvider.php
index f68ec02781..2e2f0d8adb 100644
--- a/apps/federatedfilesharing/lib/FederatedShareProvider.php
+++ b/apps/federatedfilesharing/lib/FederatedShareProvider.php
@@ -347,7 +347,9 @@ class FederatedShareProvider implements IShareProvider {
 		$query->select('*')->from($this->externalShareTable)
 			->where($query->expr()->eq('user', $query->createNamedParameter($share->getShareOwner())))
 			->andWhere($query->expr()->eq('mountpoint', $query->createNamedParameter($share->getTarget())));
-		$result = $query->execute()->fetchAll();
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		if (isset($result[0]) && (int)$result[0]['remote_id'] > 0) {
 			return $result[0];
@@ -483,7 +485,9 @@ class FederatedShareProvider implements IShareProvider {
 		$query = $this->dbConnection->getQueryBuilder();
 		$query->select('remote_id')->from('federated_reshares')
 			->where($query->expr()->eq('share_id', $query->createNamedParameter((int)$share->getId())));
-		$data = $query->execute()->fetch();
+		$result = $query->execute();
+		$data = $result->fetch();
+		$result->closeCursor();
 
 		if (!is_array($data) || !isset($data['remote_id'])) {
 			throw new ShareNotFound();
diff --git a/apps/federation/lib/DbHandler.php b/apps/federation/lib/DbHandler.php
index 365a70e2b7..ef961e90d3 100644
--- a/apps/federation/lib/DbHandler.php
+++ b/apps/federation/lib/DbHandler.php
@@ -120,8 +120,10 @@ class DbHandler {
 		$query->select('*')->from($this->dbTable)
 			->where($query->expr()->eq('id', $query->createParameter('id')))
 			->setParameter('id', $id);
-		$query->execute();
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		if (empty($result)) {
 			throw new \Exception('No Server found with ID: ' . $id);
diff --git a/apps/federation/tests/DbHandlerTest.php b/apps/federation/tests/DbHandlerTest.php
index 7a06b2c9da..ee97245874 100644
--- a/apps/federation/tests/DbHandlerTest.php
+++ b/apps/federation/tests/DbHandlerTest.php
@@ -62,7 +62,10 @@ class DbHandlerTest extends TestCase {
 		);
 
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertEmpty($result, 'we need to start with a empty trusted_servers table');
 	}
 
@@ -83,7 +86,10 @@ class DbHandlerTest extends TestCase {
 		$id = $this->dbHandler->addServer($url);
 
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame($expectedUrl, $result[0]['url']);
 		$this->assertSame($id, (int)$result[0]['id']);
@@ -104,7 +110,10 @@ class DbHandlerTest extends TestCase {
 		$id2 = $this->dbHandler->addServer('server2');
 
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(2, count($result));
 		$this->assertSame('server1', $result[0]['url']);
 		$this->assertSame('server2', $result[1]['url']);
@@ -113,7 +122,10 @@ class DbHandlerTest extends TestCase {
 
 		$this->dbHandler->removeServer($id2);
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame('server1', $result[0]['url']);
 		$this->assertSame($id1, (int)$result[0]['id']);
@@ -165,12 +177,18 @@ class DbHandlerTest extends TestCase {
 	public function XtestAddToken() {
 		$this->dbHandler->addServer('server1');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame(null, $result[0]['token']);
 		$this->dbHandler->addToken('http://server1', 'token');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame('token', $result[0]['token']);
 	}
@@ -186,12 +204,18 @@ class DbHandlerTest extends TestCase {
 	public function XtestAddSharedSecret() {
 		$this->dbHandler->addServer('server1');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame(null, $result[0]['shared_secret']);
 		$this->dbHandler->addSharedSecret('http://server1', 'secret');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame('secret', $result[0]['shared_secret']);
 	}
@@ -207,12 +231,18 @@ class DbHandlerTest extends TestCase {
 	public function testSetServerStatus() {
 		$this->dbHandler->addServer('server1');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame(TrustedServers::STATUS_PENDING, (int)$result[0]['status']);
 		$this->dbHandler->setServerStatus('http://server1', TrustedServers::STATUS_OK);
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		$this->assertSame(1, count($result));
 		$this->assertSame(TrustedServers::STATUS_OK, (int)$result[0]['status']);
 	}
diff --git a/apps/files_external/lib/Service/DBConfigService.php b/apps/files_external/lib/Service/DBConfigService.php
index eaa5815cd3..f6ccda9561 100644
--- a/apps/files_external/lib/Service/DBConfigService.php
+++ b/apps/files_external/lib/Service/DBConfigService.php
@@ -452,7 +452,10 @@ class DBConfigService {
 		$query = $builder->select($fields)
 			->from($table)
 			->where($builder->expr()->in('mount_id', $placeHolders));
-		$rows = $query->execute()->fetchAll();
+
+		$result = $query->execute();
+		$rows = $result->fetchAll();
+		$result->closeCursor();
 
 		$result = [];
 		foreach ($mountIds as $mountId) {
diff --git a/apps/files_external/tests/Service/StoragesServiceTest.php b/apps/files_external/tests/Service/StoragesServiceTest.php
index 5f10a9b949..b1118a5714 100644
--- a/apps/files_external/tests/Service/StoragesServiceTest.php
+++ b/apps/files_external/tests/Service/StoragesServiceTest.php
@@ -334,7 +334,10 @@ abstract class StoragesServiceTest extends \Test\TestCase {
 		$storageCheckQuery = $qb->select('*')
 			->from('storages')
 			->where($qb->expr()->eq('numeric_id', $qb->expr()->literal($numericId)));
-		$storages = $storageCheckQuery->execute()->fetchAll();
+
+		$result = $storageCheckQuery->execute();
+		$storages = $result->fetchAll();
+		$result->closeCursor();
 		$this->assertCount($expectedCountAfterDeletion, $storages, "expected $expectedCountAfterDeletion storages, got " . json_encode($storages));
 	}
 
diff --git a/apps/files_sharing/tests/Command/CleanupRemoteStoragesTest.php b/apps/files_sharing/tests/Command/CleanupRemoteStoragesTest.php
index dd03ffc666..b163583bf1 100644
--- a/apps/files_sharing/tests/Command/CleanupRemoteStoragesTest.php
+++ b/apps/files_sharing/tests/Command/CleanupRemoteStoragesTest.php
@@ -142,7 +142,10 @@ class CleanupRemoteStoragesTest extends TestCase {
 		$qb->select('*')
 			->from('storages')
 			->where($qb->expr()->eq('numeric_id', $qb->createNamedParameter($numericId)));
-		$result = $qb->execute()->fetchAll();
+
+		$qResult = $qb->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		if (!empty($result)) {
 			return true;
 		}
@@ -151,7 +154,10 @@ class CleanupRemoteStoragesTest extends TestCase {
 		$qb->select('*')
 			->from('filecache')
 			->where($qb->expr()->eq('storage', $qb->createNamedParameter($numericId)));
-		$result = $qb->execute()->fetchAll();
+
+		$qResult = $qb->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 		if (!empty($result)) {
 			return true;
 		}
diff --git a/apps/files_sharing/tests/Migration/SetPasswordColumnTest.php b/apps/files_sharing/tests/Migration/SetPasswordColumnTest.php
index 05cb34ac50..a0e8720d17 100644
--- a/apps/files_sharing/tests/Migration/SetPasswordColumnTest.php
+++ b/apps/files_sharing/tests/Migration/SetPasswordColumnTest.php
@@ -107,7 +107,9 @@ class SetPasswordColumnTest extends TestCase {
 		$query = $this->connection->getQueryBuilder();
 		$query->select('*')
 			->from('share');
-		$allShares = $query->execute()->fetchAll();
+		$result = $query->execute();
+		$allShares = $result->fetchAll();
+		$result->closeCursor();
 
 		foreach ($allShares as $share) {
 			if ((int)$share['share_type'] === IShare::TYPE_LINK) {
diff --git a/apps/files_trashbin/lib/Trashbin.php b/apps/files_trashbin/lib/Trashbin.php
index d0ad7eb913..7f83cbbc8a 100644
--- a/apps/files_trashbin/lib/Trashbin.php
+++ b/apps/files_trashbin/lib/Trashbin.php
@@ -994,10 +994,14 @@ class Trashbin {
 			->andWhere($query->expr()->eq('parent', $query->createNamedParameter($parentId)))
 			->andWhere($query->expr()->iLike('name', $query->createNamedParameter($pattern)));
 
+		$result = $query->execute();
+		$entries = $result->fetchAll();
+		$result->closeCursor();
+
 		/** @var CacheEntry[] $matches */
 		$matches = array_map(function (array $data) {
 			return Cache::cacheEntryFromData($data, \OC::$server->getMimeTypeLoader());
-		}, $query->execute()->fetchAll());
+		}, $entries);
 
 		foreach ($matches as $ma) {
 			if ($timestamp) {
diff --git a/apps/files_trashbin/tests/Command/CleanUpTest.php b/apps/files_trashbin/tests/Command/CleanUpTest.php
index 2984645777..f5a89be0e3 100644
--- a/apps/files_trashbin/tests/Command/CleanUpTest.php
+++ b/apps/files_trashbin/tests/Command/CleanUpTest.php
@@ -124,9 +124,13 @@ class CleanUpTest extends TestCase {
 			// if the delete operation was execute only files from user1
 			// should be left.
 			$query = $this->dbConnection->getQueryBuilder();
-			$result = $query->select('user')
-				->from($this->trashTable)
-				->execute()->fetchAll();
+			$query->select('user')
+				->from($this->trashTable);
+
+			$qResult = $query->execute();
+			$result = $qResult->fetchAll();
+			$qResult->closeCursor();
+
 			$this->assertSame(5, count($result));
 			foreach ($result as $r) {
 				$this->assertSame('user1', $r['user']);
diff --git a/apps/sharebymail/tests/ShareByMailProviderTest.php b/apps/sharebymail/tests/ShareByMailProviderTest.php
index 991d5dc021..f3e8c60fbf 100644
--- a/apps/sharebymail/tests/ShareByMailProviderTest.php
+++ b/apps/sharebymail/tests/ShareByMailProviderTest.php
@@ -545,10 +545,13 @@ class ShareByMailProviderTest extends TestCase {
 		);
 
 		$qb = $this->connection->getQueryBuilder();
-		$result = $qb->select('*')
+		$qb->select('*')
 			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
-			->execute()->fetchAll();
+			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
+
+		$qResult = $qb->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		$this->assertSame(1, count($result));
 
@@ -590,10 +593,13 @@ class ShareByMailProviderTest extends TestCase {
 		);
 
 		$qb = $this->connection->getQueryBuilder();
-		$result = $qb->select('*')
+		$qb->select('*')
 			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
-			->execute()->fetchAll();
+			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
+
+		$qResult = $qb->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		$this->assertSame(1, count($result));
 
@@ -831,7 +837,10 @@ class ShareByMailProviderTest extends TestCase {
 		$query = $this->connection->getQueryBuilder();
 		$query->select('*')->from('share')
 			->where($query->expr()->eq('id', $query->createNamedParameter($id)));
-		$before = $query->execute()->fetchAll();
+
+		$result = $query->execute();
+		$before = $result->fetchAll();
+		$result->closeCursor();
 
 		$this->assertTrue(is_array($before));
 		$this->assertSame(1, count($before));
@@ -841,7 +850,10 @@ class ShareByMailProviderTest extends TestCase {
 		$query = $this->connection->getQueryBuilder();
 		$query->select('*')->from('share')
 			->where($query->expr()->eq('id', $query->createNamedParameter($id)));
-		$after = $query->execute()->fetchAll();
+
+		$result = $query->execute();
+		$after = $result->fetchAll();
+		$result->closeCursor();
 
 		$this->assertTrue(is_array($after));
 		$this->assertEmpty($after);
@@ -861,7 +873,10 @@ class ShareByMailProviderTest extends TestCase {
 
 		$query = $this->connection->getQueryBuilder();
 		$query->select('*')->from('share');
-		$before = $query->execute()->fetchAll();
+
+		$result = $query->execute();
+		$before = $result->fetchAll();
+		$result->closeCursor();
 
 		$this->assertTrue(is_array($before));
 		$this->assertSame(2, count($before));
@@ -873,7 +888,10 @@ class ShareByMailProviderTest extends TestCase {
 
 		$query = $this->connection->getQueryBuilder();
 		$query->select('*')->from('share');
-		$after = $query->execute()->fetchAll();
+
+		$result = $query->execute();
+		$after = $result->fetchAll();
+		$result->closeCursor();
 
 		$this->assertTrue(is_array($after));
 		$this->assertSame(1, count($after));
diff --git a/lib/private/Files/Cache/Cache.php b/lib/private/Files/Cache/Cache.php
index 8a173f3519..e74cc86d9c 100644
--- a/lib/private/Files/Cache/Cache.php
+++ b/lib/private/Files/Cache/Cache.php
@@ -151,7 +151,9 @@ class Cache implements ICache {
 			$query->whereFileId($file);
 		}
 
-		$data = $query->execute()->fetch();
+		$result = $query->execute();
+		$data = $result->fetch();
+		$result->closeCursor();
 
 		//merge partial data
 		if (!$data and is_string($file) and isset($this->partial[$file])) {
@@ -220,7 +222,10 @@ class Cache implements ICache {
 				->whereParent($fileId)
 				->orderBy('name', 'ASC');
 
-			$files = $query->execute()->fetchAll();
+			$result = $query->execute();
+			$files = $result->fetchAll();
+			$result->closeCursor();
+
 			return array_map(function (array $data) {
 				return self::cacheEntryFromData($data, $this->mimetypeLoader);
 			}, $files);
@@ -467,7 +472,10 @@ class Cache implements ICache {
 			->whereStorageId()
 			->wherePath($file);
 
-		$id = $query->execute()->fetchColumn();
+		$result = $query->execute();
+		$id = $result->fetchColumn();
+		$result->closeCursor();
+
 		return $id === false ? -1 : (int)$id;
 	}
 
@@ -710,7 +718,11 @@ class Cache implements ICache {
 			->from('filecache')
 			->whereStorageId()
 			->wherePath($file);
-		$size = $query->execute()->fetchColumn();
+
+		$result = $query->execute();
+		$size = $result->fetchColumn();
+		$result->closeCursor();
+
 		if ($size !== false) {
 			if ((int)$size === -1) {
 				return self::SHALLOW;
@@ -745,9 +757,13 @@ class Cache implements ICache {
 			->whereStorageId()
 			->andWhere($query->expr()->iLike('name', $query->createNamedParameter($pattern)));
 
+		$result = $query->execute();
+		$files = $result->fetchAll();
+		$result->closeCursor();
+
 		return array_map(function (array $data) {
 			return self::cacheEntryFromData($data, $this->mimetypeLoader);
-		}, $query->execute()->fetchAll());
+		}, $files);
 	}
 
 	/**
@@ -782,9 +798,13 @@ class Cache implements ICache {
 			$query->andWhere($query->expr()->eq('mimepart', $query->createNamedParameter($mimeId, IQueryBuilder::PARAM_INT)));
 		}
 
+		$result = $query->execute();
+		$files = $result->fetchAll();
+		$result->closeCursor();
+
 		return array_map(function (array $data) {
 			return self::cacheEntryFromData($data, $this->mimetypeLoader);
-		}, $query->execute()->fetchAll());
+		}, $files);
 	}
 
 	public function searchQuery(ISearchQuery $searchQuery) {
@@ -865,7 +885,11 @@ class Cache implements ICache {
 				->whereParent($fileId)
 				->andWhere($query->expr()->lt('size', $query->createNamedParameter(0, IQueryBuilder::PARAM_INT)));
 
-			return (int)$query->execute()->fetchColumn();
+			$result = $query->execute();
+			$size = (int)$result->fetchColumn();
+			$result->closeCursor();
+
+			return $size;
 		}
 		return -1;
 	}
@@ -892,7 +916,11 @@ class Cache implements ICache {
 				->whereStorageId()
 				->whereParent($id);
 
-			if ($row = $query->execute()->fetch()) {
+			$result = $query->execute();
+			$row = $result->fetch();
+			$result->closeCursor();
+
+			if ($row) {
 				[$sum, $min] = array_values($row);
 				$sum = 0 + $sum;
 				$min = 0 + $min;
@@ -920,9 +948,13 @@ class Cache implements ICache {
 			->from('filecache')
 			->whereStorageId();
 
+		$result = $query->execute();
+		$files = $result->fetchAll(\PDO::FETCH_COLUMN);
+		$result->closeCursor();
+
 		return array_map(function ($id) {
 			return (int)$id;
-		}, $query->execute()->fetchAll(\PDO::FETCH_COLUMN));
+		}, $files);
 	}
 
 	/**
@@ -942,7 +974,11 @@ class Cache implements ICache {
 			->andWhere($query->expr()->lt('size', $query->createNamedParameter(0, IQueryBuilder::PARAM_INT)))
 			->orderBy('fileid', 'DESC');
 
-		return $query->execute()->fetchColumn();
+		$result = $query->execute();
+		$path = $result->fetchColumn();
+		$result->closeCursor();
+
+		return $path;
 	}
 
 	/**
@@ -958,7 +994,10 @@ class Cache implements ICache {
 			->whereStorageId()
 			->whereFileId($id);
 
-		$path = $query->execute()->fetchColumn();
+		$result = $query->execute();
+		$path = $result->fetchColumn();
+		$result->closeCursor();
+
 		return $path === false ? null : $path;
 	}
 
@@ -976,7 +1015,12 @@ class Cache implements ICache {
 		$query->select('path', 'storage')
 			->from('filecache')
 			->where($query->expr()->eq('fileid', $query->createNamedParameter($id, IQueryBuilder::PARAM_INT)));
-		if ($row = $query->execute()->fetch()) {
+
+		$result = $query->execute();
+		$row = $result->fetch();
+		$result->closeCursor();
+
+		if ($row) {
 			$numericId = $row['storage'];
 			$path = $row['path'];
 		} else {
diff --git a/lib/private/Files/Cache/HomeCache.php b/lib/private/Files/Cache/HomeCache.php
index e66ed7d972..f7fc806456 100644
--- a/lib/private/Files/Cache/HomeCache.php
+++ b/lib/private/Files/Cache/HomeCache.php
@@ -72,6 +72,7 @@ class HomeCache extends Cache {
 					$this->update($id, ['size' => $totalSize]);
 				}
 			}
+			$result->closeCursor();
 		}
 		return $totalSize;
 	}
diff --git a/lib/private/Files/Cache/StorageGlobal.php b/lib/private/Files/Cache/StorageGlobal.php
index 26a7be2463..8bf37514b8 100644
--- a/lib/private/Files/Cache/StorageGlobal.php
+++ b/lib/private/Files/Cache/StorageGlobal.php
@@ -61,6 +61,7 @@ class StorageGlobal {
 		while ($row = $result->fetch()) {
 			$this->cache[$row['id']] = $row;
 		}
+		$result->closeCursor();
 	}
 
 	/**
@@ -74,7 +75,10 @@ class StorageGlobal {
 				->from('storages')
 				->where($builder->expr()->eq('id', $builder->createNamedParameter($storageId)));
 
-			$row = $query->execute()->fetch();
+			$result = $query->execute();
+			$row = $result->fetch();
+			$result->closeCursor();
+
 			if ($row) {
 				$this->cache[$storageId] = $row;
 			}
diff --git a/lib/private/Files/Config/UserMountCache.php b/lib/private/Files/Config/UserMountCache.php
index 6fa9cd96bf..441a4a4532 100644
--- a/lib/private/Files/Config/UserMountCache.php
+++ b/lib/private/Files/Config/UserMountCache.php
@@ -235,7 +235,9 @@ class UserMountCache implements IUserMountCache {
 				->innerJoin('m', 'filecache', 'f', $builder->expr()->eq('m.root_id', 'f.fileid'))
 				->where($builder->expr()->eq('user_id', $builder->createPositionalParameter($user->getUID())));
 
-			$rows = $query->execute()->fetchAll();
+			$result = $query->execute();
+			$rows = $result->fetchAll();
+			$result->closeCursor();
 
 			$this->mountsForUsers[$user->getUID()] = array_filter(array_map([$this, 'dbRowToMountInfo'], $rows));
 		}
@@ -258,7 +260,9 @@ class UserMountCache implements IUserMountCache {
 			$query->andWhere($builder->expr()->eq('user_id', $builder->createPositionalParameter($user)));
 		}
 
-		$rows = $query->execute()->fetchAll();
+		$result = $query->execute();
+		$rows = $result->fetchAll();
+		$result->closeCursor();
 
 		return array_filter(array_map([$this, 'dbRowToMountInfo'], $rows));
 	}
@@ -274,7 +278,9 @@ class UserMountCache implements IUserMountCache {
 			->innerJoin('m', 'filecache', 'f', $builder->expr()->eq('m.root_id', 'f.fileid'))
 			->where($builder->expr()->eq('root_id', $builder->createPositionalParameter($rootFileId, IQueryBuilder::PARAM_INT)));
 
-		$rows = $query->execute()->fetchAll();
+		$result = $query->execute();
+		$rows = $result->fetchAll();
+		$result->closeCursor();
 
 		return array_filter(array_map([$this, 'dbRowToMountInfo'], $rows));
 	}
@@ -291,7 +297,10 @@ class UserMountCache implements IUserMountCache {
 				->from('filecache')
 				->where($builder->expr()->eq('fileid', $builder->createNamedParameter($fileId, IQueryBuilder::PARAM_INT)));
 
-			$row = $query->execute()->fetch();
+			$result = $query->execute();
+			$row = $result->fetch();
+			$result->closeCursor();
+
 			if (is_array($row)) {
 				$this->cacheInfoCache[$fileId] = [
 					(int)$row['storage'],
diff --git a/lib/private/Files/Node/Folder.php b/lib/private/Files/Node/Folder.php
index 668893f654..134455dd94 100644
--- a/lib/private/Files/Node/Folder.php
+++ b/lib/private/Files/Node/Folder.php
@@ -528,7 +528,11 @@ class Folder extends Node implements \OCP\Files\Folder {
 			->setMaxResults($limit)
 			->setFirstResult($offset);
 
-		return $query->execute()->fetchAll();
+		$result = $query->execute();
+		$rows = $result->fetchAll();
+		$result->closeCursor();
+
+		return $rows;
 	}
 
 	private function recentParse($result, $mountMap, $mimetypeLoader) {
diff --git a/lib/private/Files/Type/Loader.php b/lib/private/Files/Type/Loader.php
index d128bc724b..489ed65c22 100644
--- a/lib/private/Files/Type/Loader.php
+++ b/lib/private/Files/Type/Loader.php
@@ -123,7 +123,10 @@ class Loader implements IMimeTypeLoader {
 			->where(
 				$fetch->expr()->eq('mimetype', $fetch->createNamedParameter($mimetype)
 			));
-		$row = $fetch->execute()->fetch();
+
+		$result = $fetch->execute();
+		$row = $result->fetch();
+		$result->closeCursor();
 
 		if (!$row) {
 			throw new \Exception("Failed to get mimetype id for $mimetype after trying to store it");
@@ -141,7 +144,10 @@ class Loader implements IMimeTypeLoader {
 		$qb = $this->dbConnection->getQueryBuilder();
 		$qb->select('id', 'mimetype')
 			->from('mimetypes');
-		$results = $qb->execute()->fetchAll();
+
+		$result = $qb->execute();
+		$results = $result->fetchAll();
+		$result->closeCursor();
 
 		foreach ($results as $row) {
 			$this->mimetypes[$row['id']] = $row['mimetype'];
diff --git a/lib/private/Security/CredentialsManager.php b/lib/private/Security/CredentialsManager.php
index ace8e6889e..a40a7e1d88 100644
--- a/lib/private/Security/CredentialsManager.php
+++ b/lib/private/Security/CredentialsManager.php
@@ -84,7 +84,10 @@ class CredentialsManager implements ICredentialsManager {
 			->where($qb->expr()->eq('user', $qb->createNamedParameter((string)$userId)))
 			->andWhere($qb->expr()->eq('identifier', $qb->createNamedParameter($identifier)))
 		;
-		$result = $qb->execute()->fetch();
+
+		$qResult = $qb->execute();
+		$result = $qResult->fetch();
+		$qResult->closeCursor();
 
 		if (!$result) {
 			return null;
diff --git a/lib/private/Share/Share.php b/lib/private/Share/Share.php
index e05c4e9184..de79514300 100644
--- a/lib/private/Share/Share.php
+++ b/lib/private/Share/Share.php
@@ -194,6 +194,7 @@ class Share extends Constants {
 			}
 			$shares[] = $row;
 		}
+		$result->closeCursor();
 
 		//if didn't found a result than let's look for a group share.
 		if (empty($shares) && $user !== null) {
@@ -692,9 +693,9 @@ class Share extends Constants {
 						->from('share')
 						->where($query->expr()->eq('id', $query->createNamedParameter($row['parent'])));
 
-					$result = $query->execute();
-					$parentRow = $result->fetch();
-					$result->closeCursor();
+					$parentResult = $query->execute();
+					$parentRow = $parentResult->fetch();
+					$parentResult->closeCursor();
 
 					if ($parentRow === false) {
 						\OCP\Util::writeLog('OCP\Share', 'Can\'t select parent: ' .
diff --git a/lib/private/TagManager.php b/lib/private/TagManager.php
index 4613b6247f..155efccfaa 100644
--- a/lib/private/TagManager.php
+++ b/lib/private/TagManager.php
@@ -102,6 +102,10 @@ class TagManager implements ITagManager {
 			->andWhere($query->expr()->eq('c.type', $query->createNamedParameter($objectType)))
 			->andWhere($query->expr()->eq('c.category', $query->createNamedParameter(ITags::TAG_FAVORITE)));
 
-		return $query->execute()->fetchAll(\PDO::FETCH_COLUMN);
+		$result = $query->execute();
+		$users = $result->fetchAll(\PDO::FETCH_COLUMN);
+		$result->closeCursor();
+
+		return $users;
 	}
 }
diff --git a/lib/private/Tags.php b/lib/private/Tags.php
index 3fc66c69d6..ef901850bb 100644
--- a/lib/private/Tags.php
+++ b/lib/private/Tags.php
@@ -285,6 +285,7 @@ class Tags implements ITags {
 			$stmt = \OC_DB::prepare($sql);
 			$result = $stmt->execute([$tagId]);
 			if ($result === null) {
+				$stmt->closeCursor();
 				\OCP\Util::writeLog('core', __METHOD__. 'DB error: ' . \OC::$server->getDatabaseConnection()->getError(), ILogger::ERROR);
 				return false;
 			}
@@ -301,6 +302,7 @@ class Tags implements ITags {
 			while ($row = $result->fetchRow()) {
 				$ids[] = (int)$row['objid'];
 			}
+			$result->closeCursor();
 		}
 
 		return $ids;
@@ -538,6 +540,7 @@ class Tags implements ITags {
 						]);
 					}
 				}
+				$result->closeCursor();
 			} catch (\Exception $e) {
 				\OC::$server->getLogger()->logException($e, [
 					'message' => __METHOD__,
diff --git a/lib/private/legacy/OC_DB_StatementWrapper.php b/lib/private/legacy/OC_DB_StatementWrapper.php
index d4072caf28..4cd941c331 100644
--- a/lib/private/legacy/OC_DB_StatementWrapper.php
+++ b/lib/private/legacy/OC_DB_StatementWrapper.php
@@ -104,6 +104,15 @@ class OC_DB_StatementWrapper {
 		return $this->statement->fetchColumn($column);
 	}
 
+	/**
+	 * Closes the cursor, enabling the statement to be executed again.
+	 *
+	 * @deprecated Use Result::free() instead.
+	 */
+	public function closeCursor(): void {
+		$this->statement->closeCursor();
+	}
+
 	/**
 	 * Binds a PHP variable to a corresponding named or question mark placeholder in the
 	 * SQL statement that was use to prepare the statement.
diff --git a/lib/private/legacy/OC_Util.php b/lib/private/legacy/OC_Util.php
index cb0eef5fce..8741e55dbd 100644
--- a/lib/private/legacy/OC_Util.php
+++ b/lib/private/legacy/OC_Util.php
@@ -983,6 +983,7 @@ class OC_Util {
 			try {
 				$result = \OC_DB::executeAudited('SHOW SERVER_VERSION');
 				$data = $result->fetchRow();
+				$result->closeCursor();
 				if (isset($data['server_version'])) {
 					$version = $data['server_version'];
 					if (version_compare($version, '9.0.0', '<')) {
diff --git a/tests/lib/Accounts/AccountsManagerTest.php b/tests/lib/Accounts/AccountsManagerTest.php
index 76abeb5b49..0e086f55e4 100644
--- a/tests/lib/Accounts/AccountsManagerTest.php
+++ b/tests/lib/Accounts/AccountsManagerTest.php
@@ -248,7 +248,10 @@ class AccountsManagerTest extends TestCase {
 			->where($query->expr()->eq('uid', $query->createParameter('uid')))
 			->setParameter('uid', $uid);
 		$query->execute();
-		$result = $query->execute()->fetchAll();
+
+		$qResult = $query->execute();
+		$result = $qResult->fetchAll();
+		$qResult->closeCursor();
 
 		if (!empty($result)) {
 			return json_decode($result[0]['data'], true);
diff --git a/tests/lib/DB/ConnectionTest.php b/tests/lib/DB/ConnectionTest.php
index c8b2b7ee13..be84cb81cb 100644
--- a/tests/lib/DB/ConnectionTest.php
+++ b/tests/lib/DB/ConnectionTest.php
@@ -157,7 +157,7 @@ class ConnectionTest extends \Test\TestCase {
 		$this->assertEquals('bar', $this->getTextValueByIntergerField(1));
 	}
 
-	
+
 	public function testSetValuesOverWritePreconditionFailed() {
 		$this->expectException(\OCP\PreConditionNotMetException::class);
 
@@ -335,7 +335,7 @@ class ConnectionTest extends \Test\TestCase {
 		$this->assertEquals(0, $result);
 	}
 
-	
+
 	public function testUniqueConstraintViolating() {
 		$this->expectException(\Doctrine\DBAL\Exception\UniqueConstraintViolationException::class);
 
diff --git a/tests/lib/DB/LegacyDBTest.php b/tests/lib/DB/LegacyDBTest.php
index cf4c746a4d..d4913cbe6f 100644
--- a/tests/lib/DB/LegacyDBTest.php
+++ b/tests/lib/DB/LegacyDBTest.php
@@ -89,6 +89,8 @@ class LegacyDBTest extends \Test\TestCase {
 		$this->assertTrue((bool)$result);
 		$row = $result->fetchRow();
 		$this->assertFalse($row);
+		$result->closeCursor();
+
 		$query = OC_DB::prepare('INSERT INTO `*PREFIX*'.$this->table2.'` (`fullname`,`uri`) VALUES (?,?)');
 		$result = $query->execute(['fullname test', 'uri_1']);
 		$this->assertEquals(1, $result);
@@ -100,6 +102,7 @@ class LegacyDBTest extends \Test\TestCase {
 		$this->assertEquals($row['fullname'], 'fullname test');
 		$row = $result->fetchRow();
 		$this->assertFalse((bool)$row); //PDO returns false, MDB2 returns null
+		$result->closeCursor();
 	}
 
 	/**
@@ -112,6 +115,7 @@ class LegacyDBTest extends \Test\TestCase {
 		$query = OC_DB::prepare('SELECT `fullname`,`uri` FROM `*PREFIX*'.$this->table2.'` WHERE `uri` = ?');
 		$result = $query->execute(['uri_2']);
 		$this->assertTrue((bool)$result);
+		$result->closeCursor();
 	}
 
 	public function testUNIX_TIMESTAMP() {
@@ -121,6 +125,7 @@ class LegacyDBTest extends \Test\TestCase {
 		$query = OC_DB::prepare('SELECT `fullname`,`uri` FROM `*PREFIX*'.$this->table2.'` WHERE `uri` = ?');
 		$result = $query->execute(['uri_3']);
 		$this->assertTrue((bool)$result);
+		$result->closeCursor();
 	}
 
 	public function testLastInsertId() {
@@ -143,7 +148,12 @@ class LegacyDBTest extends \Test\TestCase {
 		$result = $query->execute([$expected, 'uri_1', 'This is a vCard']);
 		$this->assertEquals(1, $result);
 
-		$actual = OC_DB::prepare("SELECT `fullname` FROM `$table`")->execute()->fetchOne();
+		$query = OC_DB::prepare("SELECT `fullname` FROM `$table`");
+
+		$result = $query->execute();
+		$actual = $result->fetchOne();
+		$result->closeCursor();
+
 		$this->assertSame($expected, $actual);
 	}
 
@@ -162,6 +172,7 @@ class LegacyDBTest extends \Test\TestCase {
 		$result = $query->execute();
 		$this->assertTrue((bool)$result);
 		$row = $result->fetchRow();
+		$result->closeCursor();
 		$this->assertArrayHasKey($rowname, $row);
 		$this->assertEquals($expect, $row[$rowname]);
 		$query = OC_DB::prepare('DELETE FROM `' . $table . '`');
@@ -227,14 +238,17 @@ class LegacyDBTest extends \Test\TestCase {
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` LIKE ?");
 		$result = $query->execute(['foobar']);
 		$this->assertCount(0, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` ILIKE ?");
 		$result = $query->execute(['foobar']);
 		$this->assertCount(1, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` ILIKE ?");
 		$result = $query->execute(['foo']);
 		$this->assertCount(0, $result->fetchAll());
+		$result->closeCursor();
 	}
 
 	public function testILIKEWildcard() {
@@ -246,26 +260,32 @@ class LegacyDBTest extends \Test\TestCase {
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` LIKE ?");
 		$result = $query->execute(['%bar']);
 		$this->assertCount(0, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` LIKE ?");
 		$result = $query->execute(['foo%']);
 		$this->assertCount(0, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` LIKE ?");
 		$result = $query->execute(['%ba%']);
 		$this->assertCount(0, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` ILIKE ?");
 		$result = $query->execute(['%bar']);
 		$this->assertCount(1, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` ILIKE ?");
 		$result = $query->execute(['foo%']);
 		$this->assertCount(1, $result->fetchAll());
+		$result->closeCursor();
 
 		$query = OC_DB::prepare("SELECT * FROM `$table` WHERE `fullname` ILIKE ?");
 		$result = $query->execute(['%ba%']);
 		$this->assertCount(1, $result->fetchAll());
+		$result->closeCursor();
 	}
 
 	/**
@@ -282,7 +302,11 @@ class LegacyDBTest extends \Test\TestCase {
 		$result = $query->execute([$expected]);
 		$this->assertEquals(1, $result);
 
-		$actual = OC_DB::prepare("SELECT `textfield` FROM `$table`")->execute()->fetchOne();
+		$query = OC_DB::prepare("SELECT `textfield` FROM `$table`");
+
+		$result = $query->execute();
+		$actual = $result->fetchOne();
+		$result->closeCursor();
 		$this->assertSame($expected, $actual);
 	}
 
diff --git a/tests/lib/DB/QueryBuilder/ExpressionBuilderDBTest.php b/tests/lib/DB/QueryBuilder/ExpressionBuilderDBTest.php
index 8e0ce2fe93..8fd86a638f 100644
--- a/tests/lib/DB/QueryBuilder/ExpressionBuilderDBTest.php
+++ b/tests/lib/DB/QueryBuilder/ExpressionBuilderDBTest.php
@@ -67,7 +67,10 @@ class ExpressionBuilderDBTest extends TestCase {
 			->from('users')
 			->where($query->expr()->like($query->createNamedParameter($param1), $query->createNamedParameter($param2)));
 
-		$this->assertEquals($match, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals($match, $column);
 	}
 
 	public function ilikeProvider() {
@@ -101,6 +104,9 @@ class ExpressionBuilderDBTest extends TestCase {
 			->from('users')
 			->where($query->expr()->iLike($query->createNamedParameter($param1), $query->createNamedParameter($param2)));
 
-		$this->assertEquals($match, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals($match, $column);
 	}
 }
diff --git a/tests/lib/DB/QueryBuilder/FunctionBuilderTest.php b/tests/lib/DB/QueryBuilder/FunctionBuilderTest.php
index 3d9baf35b1..fad991bfa9 100644
--- a/tests/lib/DB/QueryBuilder/FunctionBuilderTest.php
+++ b/tests/lib/DB/QueryBuilder/FunctionBuilderTest.php
@@ -48,7 +48,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals('foobar', $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals('foobar', $column);
 	}
 
 	public function testMd5() {
@@ -58,7 +61,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals(md5('foobar'), $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(md5('foobar'), $column);
 	}
 
 	public function testSubstring() {
@@ -68,7 +74,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals('oo', $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals('oo', $column);
 	}
 
 	public function testSubstringNoLength() {
@@ -78,7 +87,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals('oobar', $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals('oobar', $column);
 	}
 
 	public function testLower() {
@@ -88,7 +100,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals('foobar', $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals('foobar', $column);
 	}
 
 	public function testAdd() {
@@ -98,7 +113,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals(3, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(3, $column);
 	}
 
 	public function testSubtract() {
@@ -108,7 +126,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals(1, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(1, $column);
 	}
 
 	public function testCount() {
@@ -118,7 +139,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertGreaterThan(1, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$column = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertGreaterThan(1, $column);
 	}
 
 	private function setUpMinMax($value) {
@@ -151,7 +175,10 @@ class FunctionBuilderTest extends TestCase {
 			->where($query->expr()->eq('appid', $query->createNamedParameter('minmax')))
 			->setMaxResults(1);
 
-		$this->assertEquals(null, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(null, $row);
 	}
 
 	public function testMinEmpty() {
@@ -164,7 +191,10 @@ class FunctionBuilderTest extends TestCase {
 			->where($query->expr()->eq('appid', $query->createNamedParameter('minmax')))
 			->setMaxResults(1);
 
-		$this->assertEquals(null, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(null, $row);
 	}
 
 	public function testMax() {
@@ -180,7 +210,10 @@ class FunctionBuilderTest extends TestCase {
 			->where($query->expr()->eq('appid', $query->createNamedParameter('minmax')))
 			->setMaxResults(1);
 
-		$this->assertEquals(20, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(20, $row);
 	}
 
 	public function testMin() {
@@ -196,7 +229,10 @@ class FunctionBuilderTest extends TestCase {
 			->where($query->expr()->eq('appid', $query->createNamedParameter('minmax')))
 			->setMaxResults(1);
 
-		$this->assertEquals(10, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(10, $row);
 	}
 
 	public function testGreatest() {
@@ -206,7 +242,10 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals(2, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(2, $row);
 	}
 
 	public function testLeast() {
@@ -216,6 +255,9 @@ class FunctionBuilderTest extends TestCase {
 		$query->from('appconfig')
 			->setMaxResults(1);
 
-		$this->assertEquals(1, $query->execute()->fetchColumn());
+		$result = $query->execute();
+		$row = $result->fetchColumn();
+		$result->closeCursor();
+		$this->assertEquals(1, $row);
 	}
 }
diff --git a/tests/lib/Files/Cache/QuerySearchHelperTest.php b/tests/lib/Files/Cache/QuerySearchHelperTest.php
index 8f97e0158f..8344460f75 100644
--- a/tests/lib/Files/Cache/QuerySearchHelperTest.php
+++ b/tests/lib/Files/Cache/QuerySearchHelperTest.php
@@ -136,7 +136,12 @@ class QuerySearchHelperTest extends TestCase {
 	private function search(ISearchOperator $operator) {
 		$dbOperator = $this->querySearchHelper->searchOperatorToDBExpr($this->builder, $operator);
 		$this->builder->andWhere($dbOperator);
-		return $this->builder->execute()->fetchAll(\PDO::FETCH_COLUMN);
+
+		$result = $this->builder->execute();
+		$rows = $result->fetchAll(\PDO::FETCH_COLUMN);
+		$result->closeCursor();
+
+		return $rows;
 	}
 
 	public function comparisonProvider() {
diff --git a/tests/lib/Files/Type/LoaderTest.php b/tests/lib/Files/Type/LoaderTest.php
index ccd37cbb65..fd3ec552dd 100644
--- a/tests/lib/Files/Type/LoaderTest.php
+++ b/tests/lib/Files/Type/LoaderTest.php
@@ -76,7 +76,9 @@ class LoaderTest extends \Test\TestCase {
 			->from('mimetypes')
 			->where($qb->expr()->eq('id', $qb->createPositionalParameter($mimetypeId)));
 
-		$mimetype = $qb->execute()->fetch();
+		$result = $qb->execute();
+		$mimetype = $result->fetch();
+		$result->closeCursor();
 		$this->assertEquals('testing/mymimetype', $mimetype['mimetype']);
 
 		$this->assertEquals('testing/mymimetype', $this->loader->getMimetypeById($mimetypeId));
diff --git a/tests/lib/Lock/DBLockingProviderTest.php b/tests/lib/Lock/DBLockingProviderTest.php
index ac58538284..3f53589d8f 100644
--- a/tests/lib/Lock/DBLockingProviderTest.php
+++ b/tests/lib/Lock/DBLockingProviderTest.php
@@ -102,7 +102,12 @@ class DBLockingProviderTest extends LockingProvider {
 		$query->select('lock')
 			->from('file_locks')
 			->where($query->expr()->eq('key', $query->createNamedParameter($key)));
-		return $query->execute()->fetchColumn();
+
+		$result = $query->execute();
+		$rows = $result->fetchColumn();
+		$result->closeCursor();
+
+		return $rows;
 	}
 
 	public function testDoubleShared() {