From 788ecd5ee829715889603c950a49837cf52de84b Mon Sep 17 00:00:00 2001
From: egolearner <45122959+egolearner@users.noreply.github.com>
Date: Tue, 6 Jan 2026 20:33:08 +0800
Subject: [PATCH] fix(sqlengine): reduce memory reserve size when topk is too
 big (#10)

---
 src/db/sqlengine/planner/query_planner.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/db/sqlengine/planner/query_planner.cc b/src/db/sqlengine/planner/query_planner.cc
index cfe252b..c56a364 100644
--- a/src/db/sqlengine/planner/query_planner.cc
+++ b/src/db/sqlengine/planner/query_planner.cc
@@ -617,10 +617,11 @@ Result<PlanInfo::Ptr> QueryPlanner::invert_scan(
 }
 
 int QueryPlanner::get_batch_size(const QueryInfo &info, bool has_later_filter) {
+  // ref https://arrow.apache.org/docs/developers/cpp/acero.html#batch-size
   if (!info.query_orderbys().empty() || has_later_filter) {
     return 32 * 1024;
   }
-  return info.query_topn();
+  return std::min(info.query_topn(), 32U * 1024);
 }
 
 }  // namespace zvec::sqlengine