Returns true if expr
can be evaluated using only the output of plan
.
Returns true if expr
can be evaluated using only the output of plan
. This method
can be used to determine when it is acceptable to move expression evaluation within a query
plan.
For example consider a join between two relations R(a, b) and S(c, d).
- canEvaluate(EqualTo(a,b), R)
returns true
- canEvaluate(EqualTo(a,c), R)
returns false
- canEvaluate(Literal(1), R)
returns true
as literals CAN be evaluated on any plan
Name for this rule, automatically inferred based on class name.
Name for this rule, automatically inferred based on class name.
This rule rewrites predicate sub-queries into left semi/anti joins. The following predicates are supported: a. EXISTS/NOT EXISTS will be rewritten as semi/anti join, unresolved conditions in Filter will be pulled out as the join conditions. b. IN/NOT IN will be rewritten as semi/anti join, unresolved conditions in the Filter will be pulled out as join conditions, value = selected column will also be used as join condition.