Fix Duplicated filters within (filter(TableScan)) plan for unparser

[Sevenannn]

Which issue does this PR close?

N/A

Rationale for this change

• This PR serves as an minor performance improvement for changes in Improve TableScan with filters pushdown unparsing (joins) #13132
  when rewriting plans that has aggregates with lhs / rhs with filter and scan containing same filter.

For query

        select
            c_custkey,
            count(o_orderkey)
        from
            customer left outer join orders on
                        c_custkey = o_custkey
                    and o_comment not like '%special%requests%'
        group by
            c_custkey

The logical plan is

+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| plan_type     | plan                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| logical_plan  | BytesProcessedNode                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|               |   Federated                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|               |  Projection: customer.c_custkey, count(orders.o_orderkey)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|               |   Aggregate: groupBy=[[customer.c_custkey]], aggr=[[count(orders.o_orderkey)]]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|               |     Left Join:  Filter: customer.c_custkey = orders.o_custkey                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|               |       TableScan: customer                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|               |       Filter: orders.o_comment NOT LIKE Utf8("%special%requests%")                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|               |         TableScan: orders, partial_filters=[orders.o_comment NOT LIKE Utf8("%special%requests%")]              

The rewritten query will be:
SELECT customer.c_custkey, count(orders.o_orderkey) FROM customer LEFT JOIN orders ON ((customer.c_custkey = orders.o_custkey) AND (orders.o_comment NOT LIKE '%special%requests%' AND orders.o_comment NOT LIKE '%special%requests%')) GROUP BY customer.c_custkey

Under the current approach, the filter orders.o_comment NOT LIKE Utf8("%special%requests%") will occur twice in final query, although this has no effect on query result correctness, it brings performance overhead by including duplicated conditions.

What changes are included in this PR?

• Use Vec to store filter and preserve ordering
• Check if filter exist in Vec when adding filter

Are these changes tested?

Yes

Are there any user-facing changes?

No

[jayzhan211]

Can we change them to HashSet? including table_scan_filters.

contains is O(n) operation

[Sevenannn]

Yeah my previous implementation is actually Hashset, however it doesn't preserve the filter order, so I didn't end up using Hashset

[Sevenannn]

Another thing I could do is maintain a temporary Hashset to keep track of the exsiting filters, while the results is still constructed with the Vector. Every filter will be checked if it exists with Hashset before pushing to the Vector. Would this approach be better than just using Vector.contains?

[jayzhan211]

How about IndexSet?

[alamb]

IndexSet would be better so that the order of the filters is preserved

[alamb]

Thank you @Sevenannn -- this is a great idea. Thank you @jayzhan211 for the review