nice job

The tests are missing, did you forget git add?

I try to reproduce the test case from website: https://oracle-base.com/articles/misc/rollup-cube-grouping-functions-and-grouping-sets

CREATE TABLE default.dimension_tab (fact_1_idInt32,fact_2_idInt32,fact_3_idInt32,fact_4_idInt32,sales_valueDecimal(9, 2) ) ENGINE = MergeTree ORDER BY tuple() SETTINGS index_granularity = 8192

INSERT INTO default.dimension_tab SELECT rand32(number) % 2 + 1 AS fact_1_id, rand32(number) % 5 + 1 AS fact_2_id, rand32(number) % 10 + 1 AS fact_3_id, rand32(number) % 10 + 1 AS fact_4_id, rand32(number) % 100 AS sales_value FROM system.numbers limit 1000

SELECT fact_1_id, fact_2_id, fact_3_id, SUM(sales_value) AS sales_value FROM default.dimension_tab GROUP BY GROUPING SETS((fact_1_id, fact_2_id), (fact_1_id, fact_3_id)) ORDER BY fact_1_id, fact_2_id, fact_3_id

In Oracle, the result is

FACT_1_ID FACT_2_ID FACT_3_ID SALES_VALUE GROUPING_ID

     1          1                4363.55           1
     1          2                4794.76           1
     1          3                4718.25           1
     1          4                5387.45           1
     1          5                5027.34           1
     1                     1      2737.4           2
     1                     2     1854.29           2
     1                     3     2090.96           2
     1                     4     2605.17           2
     1                     5     2590.93           2
     1                     6      2506.9           2
     1                     7     1839.85           2
     1                     8     2953.04           2
     1                     9     2778.75           2
     1                    10     2334.06           2
     2          1                5652.84           1
     2          2                4583.02           1
     2          3                5555.77           1
     2          4                5936.67           1
     2          5                4508.74           1
     2                     1     3512.69           2
     2                     2     2847.94           2
     2                     3      2972.5           2
     2                     4     2534.06           2
     2                     5     3115.99           2
     2                     6     2775.85           2
     2                     7     2208.19           2
     2                     8     2358.55           2
     2                     9     1884.11           2
     2                    10     2027.16           2

The result in this implementation:

FACT_1_ID FACT_2_ID FACT_3_ID SALES_VALUE GROUPING_ID

  0	        0      	1	4820
  0	        0      	2	5222
  0      	0      	3	5130
  0	        0	4	5426
  0      	0	5	4782
  0       	0	6	4115
  0       	0	7	5752
  0	        0	8	5385
  0      	0	9	4772
  0      	0	10	5533
  0      	1	0	8935
  0      	2	0	10974
  0      	3	0	10515
  0      	4	0	10198
  0       	5	0	10315
  1       	0	0	25256
  2      	0	0	25681

The result of this implementation is quite different from the result in Oracle. I suppose there is some issue with this implementation. Correct me if I am wrong

@KochetovNicolai Hi, KochetovNicolai, I'm trying to fix grouping sets multiple elements related issue, i wonder if we should support no parenthesis
element inside grouping sets like: GROUPING SETS(A, (A, B), (A, C)) or should only contains elements inside parenthesis like: GROUPING SETS((A), (A, B), (A, C))

@taylor12805 Hi!
I think we need to support all the cases. Query with group by grouping sets (x, (x), (y, z), ()) works in Postrges, so I think our syntax should also support it.

I'm trying to fix grouping sets multiple elements related issue

Do you need some help with it? I think I may also finish this pr, but I would really appreciate any assistance from you.

@taylor12805 Hi!
I think we need to support all the cases. Query with group by grouping sets (x, (x), (y, z), ()) works in Postrges, so I think our syntax should also support it.

I'm trying to fix grouping sets multiple elements related issue

Do you need some help with it? I think I may also finish this pr, but I would really appreciate any assistance from you.

@KochetovNicolai Hi!
I am just fixed the issue of multiple grouping sets not working correctly in AggregatingStep. There are still some remaining work in TreeRewriter part. How is urs? Let me know anywhere I can give a hand

What code changes have been done to handle the empty set with () parenthesis, at the parsing level? For example ((A),()).

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❌ MaxTheHuman
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GROUPING SETS are added in #26869