Class JoinPushExpressionsRule

All Implemented Interfaces:

@Enclosing public class JoinPushExpressionsRule extends RelRule<JoinPushExpressionsRule.Config> implements TransformationRule
Planner rule that pushes down expressions in "equal" join condition.

For example, given "emp JOIN dept ON emp.deptno + 1 = dept.deptno", adds a project above "emp" that computes the expression "emp.deptno + 1". The resulting join condition is a simple combination of AND, equals, and input fields, plus the remaining non-equal conditions.

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