SQL: Pushdown WHERE clause inside subqueries #71362
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Pinging @elastic/es-ql (Team:QL) |
costin
commented
Apr 6, 2021
| new SimplifyComparisonsArithmetics(DataTypes::areCompatible), | ||
| // prune/elimination | ||
| new PruneFilters(), | ||
| new PruneLiteralsInOrderBy(), | ||
| new PruneCast(), | ||
| new CombineLimits()); | ||
| new CombineLimits(), | ||
| new PushDownAndCombineFilters() |
There was a problem hiding this comment.
Moved the rule here to be consistent across EQL and SQL.
costin
commented
Apr 6, 2021
| @@ -189,25 +190,6 @@ protected LogicalPlan rule(Filter filter) { | |||
| } | |||
| } | |||
|
|
|||
| static class PushDownAndCombineFilters extends OptimizerRule<Filter> { | |||
There was a problem hiding this comment.
Extracted this rule from EQL inside QL project.
costin
force-pushed
the
sql/subselect-where-clause
branch
from
3c582a5 to
c161ba1
Compare
Push down filters inside subqueries, even when dealing with aggregates. The rule already existed however it was not being used inside SQL. When dealing with Aggregates, keep the aggregate functions in place but try and push down conjunctions on non-aggregates.
costin
force-pushed
the
sql/subselect-where-clause
branch
from
c161ba1 to
9a6d322
Compare
matriv
reviewed
Apr 7, 2021
There was a problem hiding this comment.
Looks good. Another very nice improvement for our subquery support!
I'd like to ask a few more tests with more complex expressions, e.g.:
group by with function:
SELECT * FROM (
SELECT languages + 1 AS lan, MAX(salary) AS max FROM test_emp WHERE languages > 1 GROUP BY lan ORDER BY 1
)
WHERE (lan - 1) > 2
aggregate with function:
SELECT * FROM (
SELECT gender, MAX(salary) / 100 AS max FROM test_emp WHERE languages > 1 GROUP BY gender ORDER BY gender
)
WHERE max > 745 AND gender IS NOT NULL
and a combination where we have both complex agg and group by:
SELECT * FROM (
SELECT lan - 1 AS lan, max / 2 AS max FROM (
SELECT languages + 1 AS lan, MAX(salary) / 10 AS max FROM test_emp WHERE languages > 1 GROUP BY lan ORDER BY 1
)
)
WHERE (lan - 1) > 1 AND max - 1000 > 2500
|
The query since it's a conjunction and thus the grouping expression is pushed down. |
bpintea
approved these changes
Apr 7, 2021
costin
added a commit
that referenced
this pull request
Apr 7, 2021
Push down filters inside subqueries, even when dealing with aggregates. The rule already existed however it was not being used inside SQL. When dealing with Aggregates, keep the aggregate functions in place but try and push down conjunctions on non-aggregates.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Push down filters inside subqueries, even when dealing with aggregates.
The rule already existed however it was not being used inside SQL.
When dealing with Aggregates, keep the aggregate functions in place but
try and push down conjunctions on non-aggregates.