morrySnow commented on code in PR #17355: URL: https://github.com/apache/doris/pull/17355#discussion_r1126274674
########## fe/fe-core/src/main/java/org/apache/doris/nereids/rules/rewrite/logical/PushdownLimit.java: ########## @@ -67,65 +74,45 @@ public List<Rule> buildRules() { LogicalUnion union = limit.child(); ImmutableList<Plan> newUnionChildren = union.children() .stream() - .map(child -> addLimit(limit, child)) + .map(child -> limit.withChildren(child)) .collect(ImmutableList.toImmutableList()); + if (union.children().equals(newUnionChildren)) { + return null; + } return limit.withChildren(union.withChildren(newUnionChildren)); }) - .toRule(RuleType.PUSH_LIMIT_THROUGH_UNION) + .toRule(RuleType.PUSH_LIMIT_THROUGH_UNION), + logicalLimit(logicalOneRowRelation()) + .then(limit -> limit.getLimit() > 0 + ? limit.child() : new LogicalEmptyRelation(limit.child().getOutput())) + .toRule(RuleType.PUSH_LIMIT_THROUGH_ONE_ROW_RELATION), + logicalLimit(logicalEmptyRelation()) + .then(UnaryNode::child) + .toRule(RuleType.PUSH_LIMIT_THROUGH_EMPTY_RELATION), Review Comment: we have a file named EliminateLimit -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For additional commands, e-mail: commits-h...@doris.apache.org