-- named_struct
SELECT named_struct("a", 1, "b", 2, "c", 3);
+------------------------------+
|named_struct(a, 1, b, 2, c, 3)|
+------------------------------+
|                     {1, 2, 3}|
+------------------------------+

-- struct
SELECT struct(1, 2, 3);
+---------------+
|struct(1, 2, 3)|
+---------------+
|      {1, 2, 3}|
+---------------+