Syntax

    1. mysql> set enable_vectorized_engine=true;
    3. mysql> select k1, k2, array_distinct(k2) from array_test;
    4. +------+-----------------------------+---------------------------+
    5. | k1   | k2                          | array_distinct(k2)        |
    6. | 1    | [1, 2, 3, 4, 5]             | [1, 2, 3, 4, 5]           |
    7. | 2    | [6, 7, 8]                   | [6, 7, 8]                 |
    9. | 4    | NULL                        | NULL                      |
    10. | 5    | [1, 2, 3, 4, 5, 4, 3, 2, 1] | [1, 2, 3, 4, 5]           |
    11. | 6    | [1, 2, 3, NULL]             | [1, 2, 3, NULL]           |
    12. | 7    | [1, 2, 3, NULL, NULL]       | [1, 2, 3, NULL, NULL]     |
    13. +------+-----------------------------+---------------------------+
    15. mysql> select k1, k2, array_distinct(k2) from array_test01;
    17. +------+------------------------------------------+---------------------------+
    18. | 1    | ['a', 'b', 'c', 'd', 'e']                | ['a', 'b', 'c', 'd', 'e'] |
    19. | 2    | ['f', 'g', 'h']                          | ['f', 'g', 'h']           |
    20. | 3    | ['']                                     | ['']                      |
    21. | 3    | [NULL]                                   | [NULL]                    |
    22. | 5    | ['a', 'b', 'c', 'd', 'e', 'a', 'b', 'c'] | ['a', 'b', 'c', 'd', 'e'] |
    23. | 6    | NULL                                     | NULL                      |
    24. | 7    | ['a', 'b', NULL]                         | ['a', 'b', NULL]          |