Use std::string_view in storage NameTo... functions

Reviewers: teon.banek

Reviewed By: teon.banek

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D2683

src/query/db_accessor.hpp

@@ -275,17 +275,15 @@ class DbAccessor final {
   }
 
   storage::PropertyId NameToProperty(const std::string_view &name) {
-    // TODO: New storage should work with string_view to avoid needless
-    // allocation.
-    return accessor_->NameToProperty(std::string(name));
+    return accessor_->NameToProperty(name);
   }
 
   storage::LabelId NameToLabel(const std::string_view &name) {
-    return accessor_->NameToLabel(std::string(name));
+    return accessor_->NameToLabel(name);
   }
 
   storage::EdgeTypeId NameToEdgeType(const std::string_view &name) {
-    return accessor_->NameToEdgeType(std::string(name));
+    return accessor_->NameToEdgeType(name);
   }
 
   const std::string &PropertyToName(storage::PropertyId prop) const {

src/storage/v2/name_id_mapper.hpp

@@ -2,6 +2,7 @@
 
 #include <atomic>
 #include <string>
+#include <string_view>
 
 #include "utils/skip_list.hpp"
 
@@ -16,8 +17,8 @@ class NameIdMapper final {
     bool operator<(const MapNameToId &other) { return name < other.name; }
     bool operator==(const MapNameToId &other) { return name == other.name; }
 
-    bool operator<(const std::string &other) { return name < other; }
-    bool operator==(const std::string &other) { return name == other; }
+    bool operator<(const std::string_view &other) { return name < other; }
+    bool operator==(const std::string_view &other) { return name == other; }
   };
 
   struct MapIdToName {
@@ -33,7 +34,7 @@ class NameIdMapper final {
 
  public:
   /// @throw std::bad_alloc if unable to insert a new mapping
-  uint64_t NameToId(const std::string &name) {
+  uint64_t NameToId(const std::string_view &name) {
     auto name_to_id_acc = name_to_id_.access();
     auto found = name_to_id_acc.find(name);
     uint64_t id;
@@ -45,7 +46,7 @@ class NameIdMapper final {
       // return an iterator to the existing item. This prevents assignment of
       // two IDs to the same name when the mapping is being inserted
       // concurrently from two threads. One ID is wasted in that case, though.
-      id = name_to_id_acc.insert({name, new_id}).first->id;
+      id = name_to_id_acc.insert({std::string(name), new_id}).first->id;
     } else {
       id = found->id;
     }
@@ -56,7 +57,7 @@ class NameIdMapper final {
     if (id_to_name_acc.find(id) == id_to_name_acc.end()) {
       // We first try to find the `id` in the map to avoid making an unnecessary
       // temporary memory allocation when the object already exists.
-      id_to_name_acc.insert({id, name});
+      id_to_name_acc.insert({id, std::string(name)});
     }
     return id;
   }

src/storage/v2/storage.cpp

@@ -625,15 +625,15 @@ const std::string &Storage::Accessor::EdgeTypeToName(
   return storage_->EdgeTypeToName(edge_type);
 }
 
-LabelId Storage::Accessor::NameToLabel(const std::string &name) {
+LabelId Storage::Accessor::NameToLabel(const std::string_view &name) {
   return storage_->NameToLabel(name);
 }
 
-PropertyId Storage::Accessor::NameToProperty(const std::string &name) {
+PropertyId Storage::Accessor::NameToProperty(const std::string_view &name) {
   return storage_->NameToProperty(name);
 }
 
-EdgeTypeId Storage::Accessor::NameToEdgeType(const std::string &name) {
+EdgeTypeId Storage::Accessor::NameToEdgeType(const std::string_view &name) {
   return storage_->NameToEdgeType(name);
 }
 
@@ -966,15 +966,15 @@ const std::string &Storage::EdgeTypeToName(EdgeTypeId edge_type) const {
   return name_id_mapper_.IdToName(edge_type.AsUint());
 }
 
-LabelId Storage::NameToLabel(const std::string &name) {
+LabelId Storage::NameToLabel(const std::string_view &name) {
   return LabelId::FromUint(name_id_mapper_.NameToId(name));
 }
 
-PropertyId Storage::NameToProperty(const std::string &name) {
+PropertyId Storage::NameToProperty(const std::string_view &name) {
   return PropertyId::FromUint(name_id_mapper_.NameToId(name));
 }
 
-EdgeTypeId Storage::NameToEdgeType(const std::string &name) {
+EdgeTypeId Storage::NameToEdgeType(const std::string_view &name) {
   return EdgeTypeId::FromUint(name_id_mapper_.NameToId(name));
 }
 

src/storage/v2/storage.hpp

@@ -265,13 +265,13 @@ class Storage final {
     const std::string &EdgeTypeToName(EdgeTypeId edge_type) const;
 
     /// @throw std::bad_alloc if unable to insert a new mapping
-    LabelId NameToLabel(const std::string &name);
+    LabelId NameToLabel(const std::string_view &name);
 
     /// @throw std::bad_alloc if unable to insert a new mapping
-    PropertyId NameToProperty(const std::string &name);
+    PropertyId NameToProperty(const std::string_view &name);
 
     /// @throw std::bad_alloc if unable to insert a new mapping
-    EdgeTypeId NameToEdgeType(const std::string &name);
+    EdgeTypeId NameToEdgeType(const std::string_view &name);
 
     bool LabelIndexExists(LabelId label) const {
       return storage_->indices_.label_index.IndexExists(label);
@@ -318,13 +318,13 @@ class Storage final {
   const std::string &EdgeTypeToName(EdgeTypeId edge_type) const;
 
   /// @throw std::bad_alloc if unable to insert a new mapping
-  LabelId NameToLabel(const std::string &name);
+  LabelId NameToLabel(const std::string_view &name);
 
   /// @throw std::bad_alloc if unable to insert a new mapping
-  PropertyId NameToProperty(const std::string &name);
+  PropertyId NameToProperty(const std::string_view &name);
 
   /// @throw std::bad_alloc if unable to insert a new mapping
-  EdgeTypeId NameToEdgeType(const std::string &name);
+  EdgeTypeId NameToEdgeType(const std::string_view &name);
 
   /// @throw std::bad_alloc
   bool CreateIndex(LabelId label);