diff --git a/app/DoctrineMigrations/Version20171008195606.php b/app/DoctrineMigrations/Version20171008195606.php
index c190f4ed3..f09726c85 100644
--- a/app/DoctrineMigrations/Version20171008195606.php
+++ b/app/DoctrineMigrations/Version20171008195606.php
@@ -31,6 +31,7 @@ class Version20171008195606 extends AbstractMigration implements ContainerAwareI
 
         switch ($this->connection->getDatabasePlatform()->getName()) {
             case 'mysql':
+                $this->addSql('UPDATE ' . $this->getTable('entry') . ' SET reading_time = 0 WHERE reading_time IS NULL;');
                 $this->addSql('ALTER TABLE ' . $this->getTable('entry') . ' CHANGE reading_time reading_time INT(11) NOT NULL;');
                 break;
             case 'postgresql':
diff --git a/tests/Wallabag/ApiBundle/Controller/EntryRestControllerTest.php b/tests/Wallabag/ApiBundle/Controller/EntryRestControllerTest.php
index 65a3ccd9a..b0d4c4e1a 100644
--- a/tests/Wallabag/ApiBundle/Controller/EntryRestControllerTest.php
+++ b/tests/Wallabag/ApiBundle/Controller/EntryRestControllerTest.php
@@ -983,7 +983,7 @@ class EntryRestControllerTest extends WallabagApiTestCase
 
         $content = json_decode($this->client->getResponse()->getContent(), true);
 
-        $this->assertSame(false, $content['exists']);
+        $this->assertFalse($content['exists']);
     }
 
     public function testGetEntriesExistsWithNoUrl()
diff --git a/tests/Wallabag/CoreBundle/GuzzleSiteAuthenticator/GrabySiteConfigBuilderTest.php b/tests/Wallabag/CoreBundle/GuzzleSiteAuthenticator/GrabySiteConfigBuilderTest.php
index 5d6a29fec..5aee9f5c0 100644
--- a/tests/Wallabag/CoreBundle/GuzzleSiteAuthenticator/GrabySiteConfigBuilderTest.php
+++ b/tests/Wallabag/CoreBundle/GuzzleSiteAuthenticator/GrabySiteConfigBuilderTest.php
@@ -68,7 +68,7 @@ class GrabySiteConfigBuilderTest extends \PHPUnit_Framework_TestCase
         $config = $this->builder->buildForHost('www.example.com');
 
         $this->assertSame('example.com', $config->getHost());
-        $this->assertSame(true, $config->requiresLogin());
+        $this->assertTrue($config->requiresLogin());
         $this->assertSame('http://www.example.com/login', $config->getLoginUri());
         $this->assertSame('login', $config->getUsernameField());
         $this->assertSame('password', $config->getPasswordField());
diff --git a/tests/Wallabag/CoreBundle/Helper/ContentProxyTest.php b/tests/Wallabag/CoreBundle/Helper/ContentProxyTest.php
index f94c21372..0731a0c0b 100644
--- a/tests/Wallabag/CoreBundle/Helper/ContentProxyTest.php
+++ b/tests/Wallabag/CoreBundle/Helper/ContentProxyTest.php
@@ -51,7 +51,7 @@ class ContentProxyTest extends \PHPUnit_Framework_TestCase
         $this->assertEmpty($entry->getMimetype());
         $this->assertEmpty($entry->getLanguage());
         $this->assertSame(0.0, $entry->getReadingTime());
-        $this->assertSame(null, $entry->getDomainName());
+        $this->assertNull($entry->getDomainName());
     }
 
     public function testWithEmptyContent()