Set start-up flag to a fix value for now

The FLAGS_query_vertex_count_to_expand_existing flag has specific
meaning for v2 related things. In v3 we king of hijacked the semantic
mening of indexing beacuse of the label-based indexing.
This caused the rule based planner to pick a not so efficient plan for
execution. with this quick fix the generated plan is correct, however
the flag is useless at this form. This will be reworked in subsequent
commits.

src/query/v2/plan/rewrite/index_lookup.hpp

@@ -17,6 +17,7 @@
 #pragma once
 
 #include <algorithm>
+#include <limits>
 #include <memory>
 #include <optional>
 #include <unordered_map>
@@ -561,8 +562,12 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
   // `max_vertex_count` controls, whether no operator should be created if the
   // vertex count in the best index exceeds this number. In such a case,
   // `nullptr` is returned and `input` is not chained.
-  std::unique_ptr<ScanAll> GenScanByIndex(const ScanAll &scan,
-                                          const std::optional<int64_t> &max_vertex_count = std::nullopt) {
+  // std::unique_ptr<ScanAll> GenScanByIndex(const ScanAll &scan, const std::optional<int64_t> &max_vertex_count =
+  // std::nullopt) {
+  std::unique_ptr<ScanAll> GenScanByIndex(const ScanAll &scan, std::optional<int64_t> max_vertex_count = std::nullopt) {
+    // debug (gvolfing)
+    max_vertex_count = std::numeric_limits<int64_t>::max();
+
     const auto &input = scan.input();
     const auto &node_symbol = scan.output_symbol_;
     const auto &view = scan.view_;

src/query/v2/request_router.hpp

@@ -437,7 +437,7 @@ class RequestRouter : public RequestRouterInterface {
   }
 
   int64_t GetApproximateVertexCount(storage::v3::LabelId label, storage::v3::PropertyId /*property*/) const override {
-    // TODO
+    // TODO(gvolfing)
     // Once we have reliable metadata to approximate the
     // vertex count -based on properties- rework this function.
     return GetApproximateVertexCount(label);