$tupleVariantType = Variant<Int32, String>;

$data = [
    <|variantValue: Variant(1,       "0", $tupleVariantType)|>,
    <|variantValue: Variant("hello", "1", $tupleVariantType)|>,
    <|variantValue: Variant(42,      "0", $tupleVariantType)|>,
];

SELECT variantValue.0 AS intAlternative, variantValue.1 AS strAlternative FROM as_table($data);