Improve performance of realm_requires_update() and make more things const

src/object-store/object_schema.cpp

@@ -60,12 +60,15 @@ ObjectSchema::ObjectSchema(Group *group, const std::string &name) : name(name) {
     }
 }
 
-Property *ObjectSchema::property_for_name(const std::string &name) {
-    for (auto& prop:properties) {
-        if (prop.name == name) {
+Property *ObjectSchema::property_for_name(StringData name) {
+    for (auto& prop : properties) {
+        if (StringData(prop.name) == name) {
             return ∝
         }
     }
     return nullptr;
 }
 
+const Property *ObjectSchema::property_for_name(StringData name) const {
+    return const_cast<ObjectSchema *>(this)->property_for_name(name);
+}

src/object-store/object_schema.hpp

@@ -19,6 +19,8 @@
 #ifndef REALM_OBJECT_SCHEMA_HPP
 #define REALM_OBJECT_SCHEMA_HPP
 
+#include <realm/string_data.hpp>
+
 #include <string>
 #include <vector>
 
@@ -39,7 +41,8 @@ namespace realm {
         std::vector<Property> properties;
         std::string primary_key;
 
-        Property *property_for_name(const std::string &name);
+        Property *property_for_name(StringData name);
+        const Property *property_for_name(StringData name) const;
         Property *primary_key_property() {
             return property_for_name(primary_key);
         }

src/object-store/object_store.cpp

@@ -337,19 +337,29 @@ bool ObjectStore::is_schema_at_version(Group *group, uint64_t version) {
     return old_version == version;
 }
 
-bool ObjectStore::realm_requires_update(Group *group, uint64_t version, Schema &schema) {
+bool ObjectStore::realm_requires_update(Group *group, uint64_t version, Schema const& schema) {
     if (!is_schema_at_version(group, version)) {
         return true;
     }
-    for (auto& target_schema : schema) {
+
+    for (auto const& target_schema : schema) {
         TableRef table = table_for_object_type(group, target_schema.name);
         if (!table) {
             return true;
         }
-    }
-    if (!indexes_are_up_to_date(group, schema)) {
+
+        // Check that all of the property indexes are up to date
+        size_t count = table->get_column_count();
+        for (size_t col = 0; col < count; ++col) {
+            StringData name = table->get_column_name(col);
+            bool is_indexed = table->has_search_index(col);
+            auto prop = target_schema.property_for_name(name);
+            if (prop && prop->requires_index() != is_indexed) {
                 return true;
             }
+        }
+    }
+
     return false;
 }
 
@@ -396,23 +406,6 @@ Schema ObjectStore::schema_from_group(Group *group) {
     return schema;
 }
 
-bool ObjectStore::indexes_are_up_to_date(Group *group, Schema &schema) {
-    for (auto &object_schema : schema) {
-        TableRef table = table_for_object_type(group, object_schema.name);
-        if (!table) {
-            continue;
-        }
-
-        update_column_mapping(group, object_schema);
-        for (auto& property : object_schema.properties) {
-            if (property.requires_index() != table->has_search_index(property.table_column)) {
-                return false;
-            }
-        }
-    }
-    return true;
-}
-
 bool ObjectStore::update_indexes(Group *group, Schema &schema) {
     bool changed = false;
     for (auto& object_schema : schema) {

src/object-store/object_store.hpp

@@ -53,7 +53,7 @@ namespace realm {
         // determines if you must call update_realm_with_schema for a given realm.
         // returns true if there is a schema version mismatch, if there tables which still need to be created,
         // or if file format or other changes/updates need to be made
-        static bool realm_requires_update(Group *group, uint64_t version, Schema &schema);
+        static bool realm_requires_update(Group *group, uint64_t version, Schema const& schema);
         
         // updates a Realm to a given target schema/version creating tables and updating indexes as necessary
         // returns if any changes were made
@@ -104,9 +104,6 @@ namespace realm {
         static std::string table_name_for_object_type(const std::string &class_name);
         static std::string object_type_for_table_name(const std::string &table_name);
 
-        // check if indexes are up to date - if false you need to call update_realm_with_schema
-        static bool indexes_are_up_to_date(Group *group, Schema &schema);
-
         // returns if any indexes were changed
         static bool update_indexes(Group *group, Schema &schema);
 

src/object-store/property.hpp

@@ -54,7 +54,7 @@ namespace realm {
         bool is_nullable = false;
 
         size_t table_column;
-        bool requires_index() { return is_primary || is_indexed; }
+        bool requires_index() const { return is_primary || is_indexed; }
     };
 
     static inline const char *string_for_property_type(PropertyType type) {

src/object-store/shared_realm.cpp

@@ -430,7 +430,7 @@ SharedRealm Realm::get_shared_realm(Config config)
     return realm;
 }
 
-bool Realm::update_schema(Schema &schema, uint64_t version)
+bool Realm::update_schema(Schema const& schema, uint64_t version)
 {
     bool changed = false;
     Config old_config(m_config);

src/object-store/shared_realm.hpp

@@ -74,7 +74,7 @@ namespace realm {
         // on the Config, and the resulting Schema and version with updated
         // column mappings are set on the realms config upon success.
         // returns if any changes were made
-        bool update_schema(Schema &schema, uint64_t version);
+        bool update_schema(Schema const& schema, uint64_t version);
 
         static uint64_t get_schema_version(Config const& config);