public LogicalPlan resolveExpressions(PartialFunction<Expression, Expression> rule) {
        return this.resolveOperators(p -> p.transformExpressions(rule));
    }
Recursively transforms the expressions of a tree, skipping nodes that have already
been analyzed.
indexr-query-opt/src/main/java/io/indexr/query/plan/logical/LogicalPlan.java