SERVER-57225 Prevent top-level AND optimization from being used for ANDs with many children

1 files changed, 5 insertions, 2 deletions

diff --git a/src/mongo/db/query/sbe_stage_builder_filter.cpp b/src/mongo/db/query/sbe_stage_builder_filter.cpp
index 0cdccc4323a..cedb52a3f5b 100644
--- a/src/mongo/db/query/sbe_stage_builder_filter.cpp
+++ b/src/mongo/db/query/sbe_stage_builder_filter.cpp
@@ -80,6 +80,7 @@ namespace mongo::stage_builder {
 namespace {
 
 struct MatchExpressionVisitorContext;
+const size_t kMaxChildrenForTopLevelAndOptimization = 25;
 
 /**
  * Output of the tree can come from two places:
@@ -131,7 +132,8 @@ struct MatchExpressionVisitorContext {
 
         // If the root node is an $and, store it in 'topLevelAnd'.
         // TODO: SERVER-50673: Revisit how we implement the top-level $and optimization.
-        if (root->matchType() == MatchExpression::AND) {
+        if (root->matchType() == MatchExpression::AND &&
+            root->numChildren() <= kMaxChildrenForTopLevelAndOptimization) {
             topLevelAnd = root;
         }
     }
@@ -165,7 +167,8 @@ struct MatchExpressionVisitorContext {
 
         // If the root node is an $and, store it in 'topLevelAnd'.
         // TODO: SERVER-50673: Revisit how we implement the top-level $and optimization.
-        if (root->matchType() == MatchExpression::AND) {
+        if (root->matchType() == MatchExpression::AND &&
+            root->numChildren() <= kMaxChildrenForTopLevelAndOptimization) {
             topLevelAnd = root;
         }
     }