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

Array<T> array_cum_sum(Array<T>)

notice

Only supported in vectorized engine

example

mysql> create table array_type_table(k1 INT, k2 Array<int>) duplicate key (k1) distributed by hash(k1) buckets 1 properties('replication_num' = '1');
mysql> insert into array_type_table values (0, []), (1, [NULL]), (2, [1, 2, 3, 4]), (3, [1, NULL, 3, NULL, 5]);
mysql> set enable_vectorized_engine = true;    # enable vectorized engine
mysql> select k2, array_cum_sum(k2) from array_type_table;
+-----------------------+-----------------------+
| k2                    | array_cum_sum(`k2`)   |
+-----------------------+-----------------------+
| []                    | []                    |
| [NULL]                | [NULL]                |
| [1, 2, 3, 4]          | [1, 3, 6, 10]         |
| [1, NULL, 3, NULL, 5] | [1, NULL, 4, NULL, 9] |
+-----------------------+-----------------------+
4 rows in set
Time: 0.122s

keywords

ARRAY,CUM_SUM,ARRAY_CUM_SUM