countequal
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:
num - value在array中的数量;
0 - value不存在数组arr中;
NULL - 如果数组为NULL。
example
mysql> select *, countEqual(c_array,5) from array_test;
+------+-----------------+--------------------------+
| id | c_array | countequal(`c_array`, 5) |
+------+-----------------+--------------------------+
| 1 | [1, 2, 3, 4, 5] | 1 |
| 2 | [6, 7, 8] | 0 |
| 3 | [] | 0 |
| 4 | NULL | NULL |
+------+-----------------+--------------------------+
mysql> select *,countEqual(c_array, 1),countEqual(c_array, 5),countEqual(c_array, NULL) from array_test;
+------+-----------------------+--------------------------+--------------------------+-----------------------------+
| id | c_array | countequal(`c_array`, 1) | countequal(`c_array`, 5) | countequal(`c_array`, NULL) |
+------+-----------------------+--------------------------+--------------------------+-----------------------------+
| 1 | [1, 2, 3, 4, 5] | 1 | 1 | 0 |
| 2 | [6, 7, 8] | 0 | 0 | 0 |
| 3 | [] | 0 | 0 | 0 |
| 4 | NULL | NULL | NULL | NULL |
| 5 | [66, 77] | 0 | 0 | 0 |
| 5 | [66, 77] | 0 | 0 | 0 |
| 6 | NULL | NULL | NULL | NULL |
| 7 | [NULL, NULL, NULL] | 0 | 0 | 3 |
| 8 | [1, 2, 3, 4, 5, 5, 5] | 1 | 3 | 0 |
+------+-----------------------+--------------------------+--------------------------+-----------------------------+
keywords
ARRAY,COUNTEQUAL