array_cum_sum

SinceVersion 2.0

array_cum_sum

description

Get the cumulative sum of an array (NULL values are skipped). If the array contains NULL values, then NULL is set at the same position in the result array.

Syntax

1. Array<T> array_cum_sum(Array<T>)

notice

Only supported in vectorized engine

example

1. mysql> create table array_type_table(k1 INT, k2 Array<int>) duplicate key (k1) distributed by hash(k1) buckets 1 properties('replication_num' = '1');
2. mysql> insert into array_type_table values (0, []), (1, [NULL]), (2, [1, 2, 3, 4]), (3, [1, NULL, 3, NULL, 5]);
3. mysql> set enable_vectorized_engine = true;    # enable vectorized engine
4. mysql> select k2, array_cum_sum(k2) from array_type_table;
5. +-----------------------+-----------------------+
6. | k2                    | array_cum_sum(`k2`)   |
7. +-----------------------+-----------------------+
8. | []                    | []                    |
9. | [NULL]                | [NULL]                |
10. | [1, 2, 3, 4]          | [1, 3, 6, 10]         |
11. | [1, NULL, 3, NULL, 5] | [1, NULL, 4, NULL, 9] |
12. +-----------------------+-----------------------+

14. 4 rows in set
15. Time: 0.122s

keywords

ARRAY,CUM_SUM,ARRAY_CUM_SUM