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9cb6dabe10
This is an improvement that tries to propagate predicates of the
nullable side of the outer join into inline view.
For example:
SELECT *
FROM functional.alltypessmall a
LEFT JOIN (
SELECT id, upper(string_col) AS upper_val,
length(string_col) AS len
FROM functional.alltypestiny
) b ON a.id = b.id
WHERE b.upper_val is NULL and b.len = 0
Before this change, the predicate b.len=0 can't be migrated into inline
view since that is on the nullable side of an outer join if the
predicate evaluates in the inline view nulls will not be rejected.
However, we can be more aggressive. In particular, some predicates that
must be evaluted at a join node can also be safely evaluted by the
outer-joined inline view. Such predicates are not marked as assigned.
The predicates propagate into the inline view and also be evaluated at
a join node.
We can divide predicates into two types. One that satisfies the condition
that same as Analyzer#canEvalPredicate can be migrated into inline view，
and one that satisfies the below three conditions is safe to be propagated
into the nullable side of an outer join.
1) The predicate needs to be bound by tupleIds.
2) The predicate is not on-clause.
3) The predicate evaluates to false when all its referenced tuples are NULL.
Therefore, 'b.upper_val is NULL' cannot be propagated to inline view but
‘b.len = 0’ can be propagated to inline view.
Tests:
* Add plan tests in inline-view.test
* One baseline plan in inline-view.test, one in nested-collections.test
and two in predicate-propagation.test had to be updated
* Ran the full set of verifications in Impala Public Jenkins
Change-Id: I6c23a45aeb5dd1aa06a95c9aa8628ecbe37ef2c1
Reviewed-on: http://gerrit.cloudera.org:8080/15047
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>