facebook/presto — pull request #1924 by nezihyigitbasi (2014-11-07 17:29:01+00:00)
Title: Array concat function

This PR implements an array concat function that supports array-to-array, element-to-array, and array-to-element concatenation.

```
select ARRAY [1,2] || ARRAY[3];
select 1 || ARRAY [2,3];
select ARRAY [1,2] || 3;
_col0
-----------
[1, 2, 3]
(1 row)
```