feat: support left-outer and left-mark hash join impl rules #274
Conversation
Not ideal, wants to unite inner, left-outer, and left-mark into one rule Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
This reverts commit 973e80c.
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
…achable!` Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
|
tpch Q13 needs a rule to push split a filter from the join node, and then the join could be turned into a left-outer hash join. Working on this now. ...
├── cond:And
│ ├── Eq
│ │ ├── #0
│ │ └── #9
│ └── Like { expr: #16, pattern: "%special%requests%", negated: true, case_insensitive: false }
|
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
We eliminate another nested loop join in TPC-H Q13 Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
| ├── PhysicalScan { table: customer } | ||
| └── PhysicalScan { table: orders } | ||
| └── PhysicalFilter { cond: Like { expr: #8, pattern: "%special%requests%", negated: true, case_insensitive: false } } |
There was a problem hiding this comment.
pushing down the filter and turn into hash join.
| ├── cond:Eq | ||
| │ ├── #1 | ||
| │ └── #14 | ||
| └── PhysicalHashJoin { join_type: LeftMark, left_keys: [ #1 ], right_keys: [ #0 ] } |
There was a problem hiding this comment.
picked up by the new hash-join-left-mark rule
| │ └── PhysicalScan { table: part } | ||
| └── PhysicalScan { table: lineitem } | ||
| └── PhysicalProjection { exprs: [ #0, #2 ] } | ||
| └── PhysicalHashJoin { join_type: LeftOuter, left_keys: [ #0 ], right_keys: [ #0 ] } |
| │ └── Eq | ||
| │ ├── #0 | ||
| │ └── #1 | ||
| └── PhysicalHashJoin { join_type: LeftOuter, left_keys: [ #0 ], right_keys: [ #0 ] } |
| ├── cond:Eq | ||
| │ ├── #0 | ||
| │ └── #11 | ||
| └── PhysicalHashJoin { join_type: LeftMark, left_keys: [ #0 ], right_keys: [ #0 ] } |
| └── PhysicalNestedLoopJoin | ||
| ├── join_type: Inner | ||
| ├── cond:And | ||
| │ ├── Gt | ||
| │ │ ├── Cast { cast_to: Float64, child: #2 } | ||
| │ │ └── #8 | ||
| │ ├── Eq | ||
| │ │ ├── #0 | ||
| │ │ └── #6 | ||
| │ └── Eq | ||
| │ ├── #1 | ||
| │ └── #7 | ||
| ├── PhysicalFilter { cond: #5 } |
There was a problem hiding this comment.
This one is a little confusing. investigating ...
yliang412
changed the title
Signed-off-by: Yuchen Liang <yuchenl3@andrew.cmu.edu>
| (Join(JoinType::Inner), child_a, child_b) | ||
| ); | ||
|
|
||
| define_rule!( |
There was a problem hiding this comment.
I don't think this rule is correct. You cannot move the outer join condition into a filter in some cases.
Consider select * from a left join b on a.x = b.y and b.z = 1. The result is different from select * from a left join b on a.x = b.y where b.z = 1. Assume left table is x=1, right table is y=1,z=2, the correct result is 1, NULL, NULL, versus the rule will produce zero rows.
There was a problem hiding this comment.
ahh, I realized that this is a filter pushdown, then it might be correct; I will do a review later :)
Problem
We should be able to convert left-outer join and left-mark logical equi join to hash join.
Summary of changes
misc
simplify_log_exprto stop usingunreachable!