diff --git a/src/Databases/Database.php b/src/Databases/Database.php
index 29429f01..95cd2e54 100644
--- a/src/Databases/Database.php
+++ b/src/Databases/Database.php
@@ -137,6 +137,7 @@ function(array $richTextArray): RichText {
     public function toArray(): array
     {
         return [
+            "object"           => "database",
             "id"               => $this->id,
             "created_time"     => $this->createdTime->format(Date::FORMAT),
             "last_edited_time" => $this->lastEditedTime->format(Date::FORMAT),
@@ -271,9 +272,10 @@ public function withoutCover(): self
         );
     }
 
-    public function withAddedProperty(string $name, PropertyInterface $property): self
+    public function addProperty(PropertyInterface $property): self
     {
         $properties = $this->properties;
+        $name = $property->property()->name();
         $properties[$name] = $property;
 
         return new self(
diff --git a/tests/Unit/Databases/DatabaseTest.php b/tests/Unit/Databases/DatabaseTest.php
new file mode 100644
index 00000000..7346c246
--- /dev/null
+++ b/tests/Unit/Databases/DatabaseTest.php
@@ -0,0 +1,236 @@
+<?php
+
+namespace Notion\Test\Unit\Databases;
+
+use Notion\Common\Date;
+use Notion\Common\Emoji;
+use Notion\Common\File;
+use Notion\Common\RichText;
+use Notion\Databases\Database;
+use Notion\Databases\DatabaseParent;
+use Notion\Databases\Properties\Title;
+use PHPUnit\Framework\TestCase;
+
+class DatabaseTest extends TestCase
+{
+    public function test_create_database(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $database = Database::create($parent);
+
+        $this->assertEquals("1ce62b6f-b7f3-4201-afd0-08acb02e61c6", $database->parent()->id());
+        $this->assertEmpty($database->properties());
+    }
+
+    public function test_add_title(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $database = Database::create($parent)->withTitle(RichText::createText("Database title"));
+
+        $this->assertEquals("Database title", $database->title()[0]->plainText());
+    }
+
+    public function test_add_icon(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $database = Database::create($parent)->withIcon(Emoji::create("⭐"));
+
+        $this->assertEquals("⭐", $database->icon()->emoji());
+    }
+
+    public function test_remove_icon(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $database = Database::create($parent)
+            ->withIcon(Emoji::create("⭐"))
+            ->withoutIcon();
+
+        $this->assertNull($database->icon());
+    }
+
+    public function test_add_cover(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $coverImage = File::createExternal("https://my-site.com/image.png");
+        $database = Database::create($parent)->withCover($coverImage);
+
+        $this->assertEquals($coverImage, $database->cover());
+    }
+
+    public function test_remove_cover(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $coverImage = File::createExternal("https://my-site.com/image.png");
+        $database = Database::create($parent)->withCover($coverImage)->withoutCover();
+
+        $this->assertNull($database->cover());
+    }
+
+    public function test_move_page(): void
+    {
+        $oldParent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $newParent = DatabaseParent::page("08da99e5-f11d-4d26-827d-112a3a9bd07d");
+        $database = Database::create($oldParent)->withParent($newParent);
+
+        $this->assertSame($newParent, $database->parent());
+    }
+
+    public function test_error_with_internal_cover_image(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $cover = FIle::createInternal("https://notion.so/image.png");
+
+        $this->expectException(\Exception::class);
+        Database::create($parent)->withCover($cover);
+    }
+
+    public function test_replace_properties(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $properties = [
+            "Dummy prop name" => Title::create("Dummy prop name")
+        ];
+        $database = Database::create($parent)->withProperties($properties);
+
+        $this->assertCount(1, $database->properties());
+    }
+
+    public function test_add_property(): void
+    {
+        $parent = DatabaseParent::page("1ce62b6f-b7f3-4201-afd0-08acb02e61c6");
+        $database = Database::create($parent)->addProperty(
+            Title::create("Dummy prop name")
+        );
+
+        $this->assertCount(1, $database->properties());
+    }
+
+    public function test_array_conversion(): void
+    {
+        $array = [
+            "object" => "database",
+            "id" => "a7e80c0b-a766-43c3-a9e9-21ce94595e0e",
+            "created_time" => "2020-12-08T12:00:00.000000Z",
+            "last_edited_time" => "2020-12-08T12:00:00.000000Z",
+            "title" => [[
+                "plain_text" => "Page title",
+                "href" => null,
+                "annotations" => [
+                    "bold"          => false,
+                    "italic"        => false,
+                    "strikethrough" => false,
+                    "underline"     => false,
+                    "code"          => false,
+                    "color"         => "default",
+                ],
+                "type" => "text",
+                "text" => [ "content" => "Database title", "link" => null ],
+            ]],
+            "icon" => null,
+            "cover" => null,
+            "properties" => [
+                "title" => [
+                    "id"    => "title",
+                    "name"  => "Dummy prop name",
+                    "type"  => "title",
+                    "title" => [],
+                ],
+            ],
+            "parent" => [
+                "type" => "page_id",
+                "page_id" => "1ce62b6f-b7f3-4201-afd0-08acb02e61c6",
+            ],
+            "url" => "https://notion.so/a7e80c0ba76643c3a9e921ce94595e0e",
+        ];
+        $database = Database::fromArray($array);
+
+        $outArray = $array;
+        unset($outArray["parent"]["type"]);
+
+        $this->assertSame($outArray, $database->toArray());
+        $this->assertSame("a7e80c0b-a766-43c3-a9e9-21ce94595e0e", $database->id());
+        $this->assertSame("https://notion.so/a7e80c0ba76643c3a9e921ce94595e0e", $database->url());
+        $this->assertEquals(
+            "2020-12-08T12:00:00.000000Z",
+            $database->createdTime()->format(Date::FORMAT),
+        );
+        $this->assertEquals(
+            "2020-12-08T12:00:00.000000Z",
+            $database->lastEditedTime()->format(Date::FORMAT),
+        );
+    }
+
+    public function test_from_array_with_emoji_icon(): void
+    {
+        $array = [
+            "id" => "a7e80c0b-a766-43c3-a9e9-21ce94595e0e",
+            "created_time" => "2020-12-08T12:00:00.000000Z",
+            "last_edited_time" => "2020-12-08T12:00:00.000000Z",
+            "title" => [[
+                "plain_text" => "Page title",
+                "href" => null,
+                "annotations" => [
+                    "bold"          => false,
+                    "italic"        => false,
+                    "strikethrough" => false,
+                    "underline"     => false,
+                    "code"          => false,
+                    "color"         => "default",
+                ],
+                "type" => "text",
+                "text" => [ "content" => "Database title", "link" => null ],
+            ]],
+            "icon" => [
+                "type" => "emoji",
+                "emoji" => "⭐",
+            ],
+            "cover" => null,
+            "properties" => [],
+            "parent" => [
+                "type" => "page_id",
+                "page_id" => "1ce62b6f-b7f3-4201-afd0-08acb02e61c6",
+            ],
+            "url" => "https://notion.so/a7e80c0ba76643c3a9e921ce94595e0e",
+        ];
+        $database = Database::fromArray($array);
+
+        $this->assertEquals("⭐", $database->icon()->emoji());
+    }
+
+    public function test_from_array_with_file_icon(): void
+    {
+        $array = [
+            "id" => "a7e80c0b-a766-43c3-a9e9-21ce94595e0e",
+            "created_time" => "2020-12-08T12:00:00.000000Z",
+            "last_edited_time" => "2020-12-08T12:00:00.000000Z",
+            "title" => [[
+                "plain_text" => "Page title",
+                "href" => null,
+                "annotations" => [
+                    "bold"          => false,
+                    "italic"        => false,
+                    "strikethrough" => false,
+                    "underline"     => false,
+                    "code"          => false,
+                    "color"         => "default",
+                ],
+                "type" => "text",
+                "text" => [ "content" => "Database title", "link" => null ],
+            ]],
+            "icon" => [
+                "type" => "external",
+                "external" => [ "url" => "https://my-site.com/image.png" ],
+            ],
+            "cover" => null,
+            "properties" => [],
+            "parent" => [
+                "type" => "page_id",
+                "page_id" => "1ce62b6f-b7f3-4201-afd0-08acb02e61c6",
+            ],
+            "url" => "https://notion.so/a7e80c0ba76643c3a9e921ce94595e0e",
+        ];
+        $database = Database::fromArray($array);
+
+        $this->assertEquals("https://my-site.com/image.png", $database->icon()->url());
+    }
+}