diff --git a/flex/engines/graph_db/runtime/common/context.cc b/flex/engines/graph_db/runtime/common/context.cc
index 5a01d79078c3..11d6edf5c54b 100644
--- a/flex/engines/graph_db/runtime/common/context.cc
+++ b/flex/engines/graph_db/runtime/common/context.cc
@@ -161,10 +161,8 @@ const std::shared_ptr<IContextColumn> Context::get(int alias) const {
     return head;
   }
   assert(static_cast<size_t>(alias) < columns.size());
-  {
-    assert(columns[alias] != nullptr);
-    return columns[alias];
-  }
+  // return nullptr if the column is not set
+  return columns[alias];
 }
 
 size_t Context::row_num() const {
diff --git a/flex/engines/graph_db/runtime/common/operators/intersect.cc b/flex/engines/graph_db/runtime/common/operators/intersect.cc
index e4e7a9c6e9e7..ec98818c5359 100644
--- a/flex/engines/graph_db/runtime/common/operators/intersect.cc
+++ b/flex/engines/graph_db/runtime/common/operators/intersect.cc
@@ -134,6 +134,7 @@ static Context intersect_impl(std::vector<Context>&& ctxs, int key) {
                   return idx_col1.get_value(a) < idx_col1.get_value(b);
                 });
       std::vector<size_t> shuffle_offsets;
+      std::vector<size_t> shuffle_offsets_1;
       size_t idx0 = 0, idx1 = 0;
       while (idx0 < idx_col0.size() && idx1 < idx_col1.size()) {
         if (idx_col0.get_value(offsets0[idx0]) <
@@ -151,6 +152,7 @@ static Context intersect_impl(std::vector<Context>&& ctxs, int key) {
             auto v1 = vlist1.get_vertex(offsets1[idx1]);
             if (v0 == v1) {
               shuffle_offsets.push_back(offsets0[idx0]);
+              shuffle_offsets_1.push_back(offsets1[idx1]);
             } else if (v0 < v1) {
               break;
             } else {
@@ -164,7 +166,13 @@ static Context intersect_impl(std::vector<Context>&& ctxs, int key) {
       }
 
       ctxs[0].reshuffle(shuffle_offsets);
+      ctxs[1].reshuffle(shuffle_offsets_1);
       ctxs[0].pop_idx_col();
+      for (size_t i = 0; i < ctxs[1].col_num(); ++i) {
+        if (i >= ctxs[0].col_num() || ctxs[0].get(i) == nullptr) {
+          ctxs[0].set(i, ctxs[1].get(i));
+        }
+      }
       return ctxs[0];
     }
   }