What is the bug?
If a field that contains array values is used in a GROUP BY clause, each value in the array is considered as a separate row value.

Consider an index with the following data:

{1, [1, 2]}
{2, [3, 4]}
{3, [1, 5]}
{4, [1, 2]}
{5, [2, 3]}

and this query:

SELECT COUNT(x), y FROM test3 GROUP BY y;
{3, 1}
{3, 2}
{2, 3}
{1, 4}
{1, 5}

The expected results are:

{2, [1, 2]}
{1, [3, 4]}
{1, [1, 5]}
{1, [2, 3]}

How can one reproduce the bug?
Steps to reproduce the behavior:

1. Load the data above into a new index
2. Run the query above on the index

What is the expected behavior?
Preserve the array value and perform comparisons on the array value as a whole. Only group rows that have the same array values.

What is your host/environment?

• OS: MacOS (should not matter)
• Version [e.g. 3.0 code base]
• Plugins: SQL plugin

Do you have any screenshots?
N/A

Do you have any additional context?
Issue #1300 had a change recently merged in that allows array values to be used in query evaluation and in the result set.