-- Disabled query_plan_remove_redundant_distinct
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Distinct
          Distinct (Preliminary DISTINCT)
            Expression ((Before ORDER BY + Projection))
              Distinct
                Distinct (Preliminary DISTINCT)
                  Expression (Before ORDER BY)
                    ReadFromSystemNumbers
-- Enabled query_plan_remove_redundant_distinct
-- DISTINCT is only in most inner subquery
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT *
    FROM
    (
        SELECT DISTINCT *
        FROM numbers(3)
    )
)
-- explain
Expression ((Projection + (Before ORDER BY + (Projection + (Before ORDER BY + Projection)))))
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression (Before ORDER BY)
        ReadFromSystemNumbers
-- execute
0
1
2
-- do _not_ remove DISTINCT after UNION
-- query
SELECT DISTINCT number FROM
(
    (SELECT DISTINCT number FROM numbers(1))
    UNION ALL
    (SELECT DISTINCT number FROM numbers(2))
)
ORDER BY number
-- explain
Expression (Projection)
  Distinct
    Sorting (Sorting for ORDER BY)
      Distinct (Preliminary DISTINCT)
        Union
          Expression ((Before ORDER BY + Projection))
            Distinct
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromSystemNumbers
          Expression (( + Projection))
            Distinct
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromSystemNumbers
-- execute
0
1
-- do _not_ remove DISTINCT after JOIN
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT number AS n
    FROM numbers(2)
) as x,
(
    SELECT DISTINCT number AS n
    FROM numbers(2)
) as y
ORDER BY x.n, y.n
-- explain
Expression (Projection)
  Distinct
    Sorting (Sorting for ORDER BY)
      Distinct (Preliminary DISTINCT)
        Expression (Before ORDER BY)
          Join (JOIN FillRightFirst)
            Expression ((Before JOIN + Projection))
              Distinct
                Distinct (Preliminary DISTINCT)
                  Expression (Before ORDER BY)
                    ReadFromSystemNumbers
            Expression ((Joined actions + (Rename joined columns + Projection)))
              Distinct
                Distinct (Preliminary DISTINCT)
                  Expression (Before ORDER BY)
                    ReadFromSystemNumbers
-- execute
0	0
0	1
1	0
1	1
-- DISTINCT duplicates with several columns
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT *
    FROM
    (
        SELECT DISTINCT number as a, 2*number as b
        FROM numbers(3)
    )
)
ORDER BY a, b
-- explain
Expression (Projection)
  Sorting (Sorting for ORDER BY)
    Expression ((Before ORDER BY + (Projection + (Before ORDER BY + Projection))))
      Distinct
        Distinct (Preliminary DISTINCT)
          Expression (Before ORDER BY)
            ReadFromSystemNumbers
-- execute
0	0
1	2
2	4
-- DISTINCT duplicates with constant columns
-- query
SELECT DISTINCT 2, a, b
FROM
(
    SELECT DISTINCT a, b
    FROM
    (
        SELECT DISTINCT 1, number as a, 2*number as b
        FROM numbers(3)
    )
)
ORDER BY a, b
-- explain
Expression (Projection)
  Sorting (Sorting for ORDER BY)
    Expression ((Before ORDER BY + (Projection + (Before ORDER BY + Projection))))
      Distinct
        Distinct (Preliminary DISTINCT)
          Expression (Before ORDER BY)
            ReadFromSystemNumbers
-- execute
2	0	0
2	1	2
2	2	4
-- ARRAY JOIN: do _not_ remove outer DISTINCT because new rows are generated between inner and outer DISTINCTs
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT *
    FROM VALUES('Hello', 'World', 'Goodbye')
) AS words
ARRAY JOIN [0, 1] AS arr
ORDER BY c1, arr
-- explain
Expression (Projection)
  Distinct
    Sorting (Sorting for ORDER BY)
      Distinct (Preliminary DISTINCT)
        Expression (Before ORDER BY)
          ArrayJoin (ARRAY JOIN)
            Expression ((Before ARRAY JOIN + Projection))
              Distinct
                Distinct (Preliminary DISTINCT)
                  Expression (Before ORDER BY)
                    ReadFromStorage (Values)
-- execute
Goodbye
Hello
World
-- WITH FILL: do _not_ remove outer DISTINCT because new rows are generated between inner and outer DISTINCTs
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT *
    FROM values('id UInt8', 0, 2)
    ORDER BY id ASC WITH FILL
)
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Filling
          Distinct
            Sorting (Sorting for ORDER BY)
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromStorage (Values)
-- execute
0
1
2
-- WHERE with arrayJoin(): do _not_ remove outer DISTINCT because new rows are generated between inner and outer DISTINCTs
-- query
SELECT DISTINCT *
FROM
(
    SELECT DISTINCT ['Istanbul', 'Berlin', 'Bensheim'] AS cities
)
WHERE arrayJoin(cities) IN ['Berlin', 'Bensheim']
ORDER BY cities
-- explain
Expression (( + Projection))
  Distinct
    Sorting (Sorting for ORDER BY)
      Distinct (Preliminary DISTINCT)
        Expression (Before ORDER BY)
          Filter ((WHERE + Projection))
            Distinct
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromStorage (SystemOne)
-- execute
['Istanbul','Berlin','Bensheim']
-- GROUP BY before DISTINCT with on the same columns => remove DISTINCT
-- query
SELECT DISTINCT a
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a
    ORDER BY a
)
-- explain
Expression ((Projection + (Before ORDER BY + Projection)))
  Sorting (Sorting for ORDER BY)
    Expression (Before ORDER BY)
      Aggregating
        Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
          Join (JOIN FillRightFirst)
            Expression (Before JOIN)
              ReadFromSystemNumbers
            Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
              ReadFromSystemNumbers
-- execute
0
1
2
-- GROUP BY before DISTINCT with on different columns => do _not_ remove DISTINCT
-- query
SELECT DISTINCT c
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a
    ORDER BY a
)
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Sorting (Sorting for ORDER BY)
          Expression (Before ORDER BY)
            Aggregating
              Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
                Join (JOIN FillRightFirst)
                  Expression (Before JOIN)
                    ReadFromSystemNumbers
                  Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                    ReadFromSystemNumbers
-- execute
12
-- GROUP BY WITH ROLLUP before DISTINCT with on different columns => do _not_ remove DISTINCT
-- query
SELECT DISTINCT c
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH ROLLUP
    ORDER BY a
)
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Sorting (Sorting for ORDER BY)
          Expression (Before ORDER BY)
            Rollup
              Aggregating
                Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
                  Join (JOIN FillRightFirst)
                    Expression (Before JOIN)
                      ReadFromSystemNumbers
                    Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                      ReadFromSystemNumbers
-- execute
12
36
-- GROUP BY WITH ROLLUP before DISTINCT with on the same columns => remove DISTINCT
-- query
SELECT DISTINCT a
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH ROLLUP
    ORDER BY a
)
-- explain
Expression ((Projection + (Before ORDER BY + Projection)))
  Sorting (Sorting for ORDER BY)
    Expression (Before ORDER BY)
      Rollup
        Aggregating
          Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
            Join (JOIN FillRightFirst)
              Expression (Before JOIN)
                ReadFromSystemNumbers
              Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                ReadFromSystemNumbers
-- execute
0
0
1
2
-- GROUP BY WITH CUBE before DISTINCT with on different columns => do _not_ remove DISTINCT
-- query
SELECT DISTINCT c
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH CUBE
    ORDER BY a
)
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Sorting (Sorting for ORDER BY)
          Expression (Before ORDER BY)
            Cube
              Aggregating
                Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
                  Join (JOIN FillRightFirst)
                    Expression (Before JOIN)
                      ReadFromSystemNumbers
                    Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                      ReadFromSystemNumbers
-- execute
12
36
-- GROUP BY WITH CUBE before DISTINCT with on the same columns => remove DISTINCT
-- query
SELECT DISTINCT a
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH CUBE
    ORDER BY a
)
-- explain
Expression ((Projection + (Before ORDER BY + Projection)))
  Sorting (Sorting for ORDER BY)
    Expression (Before ORDER BY)
      Cube
        Aggregating
          Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
            Join (JOIN FillRightFirst)
              Expression (Before JOIN)
                ReadFromSystemNumbers
              Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                ReadFromSystemNumbers
-- execute
0
0
1
2
-- GROUP BY WITH TOTALS before DISTINCT with on different columns => do _not_ remove DISTINCT
-- query
SELECT DISTINCT c
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH TOTALS
    ORDER BY a
)
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression ((Before ORDER BY + Projection))
        Sorting (Sorting for ORDER BY)
          Expression (Before ORDER BY)
            TotalsHaving
              Aggregating
                Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
                  Join (JOIN FillRightFirst)
                    Expression (Before JOIN)
                      ReadFromSystemNumbers
                    Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                      ReadFromSystemNumbers
-- execute
12

36
-- GROUP BY WITH TOTALS before DISTINCT with on the same columns => remove DISTINCT
-- query
SELECT DISTINCT a
FROM
(
    SELECT
        a,
        sum(b) AS c
    FROM
    (
        SELECT
            x.number AS a,
            y.number AS b
        FROM numbers(3) AS x, numbers(3, 3) AS y
    )
    GROUP BY a WITH TOTALS
    ORDER BY a
)
-- explain
Expression ((Projection + (Before ORDER BY + Projection)))
  Sorting (Sorting for ORDER BY)
    Expression (Before ORDER BY)
      TotalsHaving
        Aggregating
          Expression ((Before GROUP BY + (Projection + Before ORDER BY)))
            Join (JOIN FillRightFirst)
              Expression (Before JOIN)
                ReadFromSystemNumbers
              Expression ((Joined actions + (Rename joined columns + (Projection + Before ORDER BY))))
                ReadFromSystemNumbers
-- execute
0
1
2

0
-- DISTINCT COUNT() with GROUP BY => do _not_ remove DISTINCT
-- query
select distinct count() from numbers(10) group by number
-- explain
Expression (Projection)
  Distinct
    Distinct (Preliminary DISTINCT)
      Expression (Before ORDER BY)
        Aggregating
          Expression (Before GROUP BY)
            ReadFromSystemNumbers
-- execute
1
-- UNION ALL with DISTINCT => do _not_ remove DISTINCT
-- query
SELECT DISTINCT number
FROM
(
    SELECT DISTINCT number
    FROM numbers(1)
    UNION ALL
    SELECT DISTINCT number
    FROM numbers(2)
)
ORDER BY number
-- explain
Expression (Projection)
  Distinct
    Sorting (Sorting for ORDER BY)
      Distinct (Preliminary DISTINCT)
        Union
          Expression ((Before ORDER BY + Projection))
            Distinct
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromSystemNumbers
          Expression (( + Projection))
            Distinct
              Distinct (Preliminary DISTINCT)
                Expression (Before ORDER BY)
                  ReadFromSystemNumbers
-- execute
0
1