diff --git a/fiable_db.py b/fiable_db.py
index 81df04b..cad944e 100644
--- a/fiable_db.py
+++ b/fiable_db.py
@@ -37,6 +37,7 @@ def get_next_id(table: str = "default") -> int:
             return row["id"]
         else:
             return current_id
+
     last_id = reduce(get_id, database[::-1], None)
     # Return the next id, or 1 if there is no last id
     return last_id + 1 if last_id else 1
diff --git a/test/test_update.py b/test/test_update.py
new file mode 100644
index 0000000..6d85faf
--- /dev/null
+++ b/test/test_update.py
@@ -0,0 +1,192 @@
+from fiable_db import start, add, update, get_database
+
+
+def test_update_simple():
+    """Test update in the default table."""
+    start()
+    add(
+        [
+            {"name": "Noelia", "age": 34, "height": 165},
+            {"name": "Juan", "age": 41, "height": 187},
+            {"name": "Valentina", "age": 12, "height": 142},
+        ]
+    )
+    update(2, {"age": 99})
+    assert get_database() == [
+        {
+            "id": 1,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 165},
+        },
+        {
+            "id": 2,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Juan", "age": 41, "height": 187},
+        },
+        {
+            "id": 3,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Valentina", "age": 12, "height": 142},
+        },
+        {
+            "id": 2,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Juan", "age": 99, "height": 187},
+        },
+    ]
+    update(2, {"name": "Cristo"})
+    assert get_database() == [
+        {
+            "id": 1,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 165},
+        },
+        {
+            "id": 2,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Juan", "age": 41, "height": 187},
+        },
+        {
+            "id": 3,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Valentina", "age": 12, "height": 142},
+        },
+        {
+            "id": 2,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Juan", "age": 99, "height": 187},
+        },
+        {
+            "id": 2,
+            "rev": 3,
+            "table": "default",
+            "data": {"name": "Cristo", "age": 99, "height": 187},
+        },
+    ]
+    update(1, {"height": 150})
+    assert get_database() == [
+        {
+            "id": 1,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 165},
+        },
+        {
+            "id": 2,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Juan", "age": 41, "height": 187},
+        },
+        {
+            "id": 3,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Valentina", "age": 12, "height": 142},
+        },
+        {
+            "id": 2,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Juan", "age": 99, "height": 187},
+        },
+        {
+            "id": 2,
+            "rev": 3,
+            "table": "default",
+            "data": {"name": "Cristo", "age": 99, "height": 187},
+        },
+        {
+            "id": 1,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 150},
+        },
+    ]
+
+
+def test_update_table():
+    """Test update in a table."""
+    add({"name": "Antony", "age": 77, "height": 188}, table="users")
+    update(1, {"age": 99}, table="users")
+    assert get_database() == [
+        {
+            "id": 1,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 165},
+        },
+        {
+            "id": 2,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Juan", "age": 41, "height": 187},
+        },
+        {
+            "id": 3,
+            "rev": 1,
+            "table": "default",
+            "data": {"name": "Valentina", "age": 12, "height": 142},
+        },
+        {
+            "id": 2,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Juan", "age": 99, "height": 187},
+        },
+        {
+            "id": 2,
+            "rev": 3,
+            "table": "default",
+            "data": {"name": "Cristo", "age": 99, "height": 187},
+        },
+        {
+            "id": 1,
+            "rev": 2,
+            "table": "default",
+            "data": {"name": "Noelia", "age": 34, "height": 150},
+        },
+        {
+            "id": 1,
+            "rev": 1,
+            "table": "users",
+            "data": {"name": "Antony", "age": 77, "height": 188},
+        },
+        {
+            "id": 1,
+            "rev": 2,
+            "table": "users",
+            "data": {"name": "Antony", "age": 99, "height": 188},
+        },
+    ]
+  
+def test_update_table_not_exists():
+    """Test update in a table that not exists."""
+    pass
+
+def test_update_id_not_exists():
+    """Test update with an id that not exists."""
+    pass
+
+def test_update_multiple_values_default():
+    """Test update multiple values in the default table."""
+    pass
+
+def test_update_multiple_values_table():
+    """Test update multiple values in a table."""
+    pass
+
+def test_update_with_keys_not_exists():
+    """Test update with keys that not exists."""
+    pass
+
+def test_update_with_force():
+    """Test update with force."""
+    pass