countequal

SinceVersion 1.2.0

countequal

description

Syntax

BIGINT countequal(ARRAY<T> arr, T value)

判断数组中包含value元素的个数。返回结果如下：

1. num      - value在array中的数量；
2. 0        - value不存在数组arr中；
3. NULL     - 如果数组为NULL。

notice

仅支持向量化引擎中使用

example

1. mysql> set enable_vectorized_engine=true;

3. mysql> select *, countEqual(c_array,5) from array_test;
4. +------+-----------------+--------------------------+
5. | id   | c_array         | countequal(`c_array`, 5) |
6. +------+-----------------+--------------------------+
7. |    1 | [1, 2, 3, 4, 5] |                        1 |
8. |    2 | [6, 7, 8]       |                        0 |
9. |    3 | []              |                        0 |
10. |    4 | NULL            |                     NULL |
11. +------+-----------------+--------------------------+

13. mysql> select *,countEqual(c_array, 1),countEqual(c_array, 5),countEqual(c_array, NULL) from array_test;
14. +------+-----------------------+--------------------------+--------------------------+-----------------------------+
15. | id   | c_array               | countequal(`c_array`, 1) | countequal(`c_array`, 5) | countequal(`c_array`, NULL) |
16. +------+-----------------------+--------------------------+--------------------------+-----------------------------+
17. |    1 | [1, 2, 3, 4, 5]       |                        1 |                        1 |                           0 |
18. |    2 | [6, 7, 8]             |                        0 |                        0 |                           0 |
19. |    3 | []                    |                        0 |                        0 |                           0 |
20. |    4 | NULL                  |                     NULL |                     NULL |                        NULL |
21. |    5 | [66, 77]              |                        0 |                        0 |                           0 |
22. |    5 | [66, 77]              |                        0 |                        0 |                           0 |
23. |    6 | NULL                  |                     NULL |                     NULL |                        NULL |
24. |    7 | [NULL, NULL, NULL]    |                        0 |                        0 |                           3 |
25. |    8 | [1, 2, 3, 4, 5, 5, 5] |                        1 |                        3 |                           0 |
26. +------+-----------------------+--------------------------+--------------------------+-----------------------------+

keywords

ARRAY,COUNTEQUAL