Syntax

    1. mysql> set enable_vectorized_engine=true;
    3. +------+-----------+------------+
    4. | k1   | k2        | size(`k2`) |
    6. |    1 | [1, 2, 3] |          3 |
    7. |    2 | []        |          0 |
    8. |    3 | NULL      |       NULL |
    9. +------+-----------+------------+
    11. +------+-----------+-------------------+
    12. | k1   | k2        | cardinality(`k2`) |
    13. +------+-----------+-------------------+
    14. |    1 | [1, 2, 3] |                 3 |
    15. |    2 | []        |                 0 |