diff --git a/lib/tapioca/dsl/compilers/identity_cache.rb b/lib/tapioca/dsl/compilers/identity_cache.rb
index 5c1629f28..4a2dfbe81 100644
--- a/lib/tapioca/dsl/compilers/identity_cache.rb
+++ b/lib/tapioca/dsl/compilers/identity_cache.rb
@@ -131,7 +131,7 @@ def create_fetch_by_methods(field, klass)
           is_cache_index = field.instance_variable_defined?(:@attribute_proc)
 
           # Both `cache_index` and `cache_attribute` generate aliased methods
-          create_aliased_fetch_by_methods(field, klass)
+          create_aliased_fetch_by_methods(field, klass, is_cache_index: is_cache_index)
 
           # If the method used was `cache_index` a few extra methods are created
           create_index_fetch_by_methods(field, klass) if is_cache_index
@@ -182,8 +182,8 @@ def create_index_fetch_by_methods(field, klass)
           )
         end
 
-        #: (untyped field, RBI::Scope klass) -> void
-        def create_aliased_fetch_by_methods(field, klass)
+        #: (untyped field, RBI::Scope klass, is_cache_index: bool) -> void
+        def create_aliased_fetch_by_methods(field, klass, is_cache_index:)
           type, _ = Helpers::ActiveRecordColumnTypeHelper.new(
             constant,
             column_type_option: Helpers::ActiveRecordColumnTypeHelper::ColumnTypeOption::Nilable,
@@ -195,6 +195,15 @@ def create_aliased_fetch_by_methods(field, klass)
             create_param(arg.to_s, type: "T.untyped")
           end
 
+          multi_value_type =
+            if field.unique
+              type
+            elsif is_cache_index
+              COLLECTION_TYPE.call(multi_type)
+            else
+              COLLECTION_TYPE.call(type)
+            end
+
           klass.create_method(
             "fetch_#{suffix}",
             class_method: true,
@@ -206,7 +215,7 @@ def create_aliased_fetch_by_methods(field, klass)
             "fetch_multi_#{suffix}",
             class_method: true,
             parameters: [create_param("keys", type: "T::Enumerable[T.untyped]")],
-            return_type: COLLECTION_TYPE.call(multi_type),
+            return_type: "T::Hash[T.untyped, #{multi_value_type}]",
           )
         end
       end
diff --git a/spec/tapioca/dsl/compilers/identity_cache_spec.rb b/spec/tapioca/dsl/compilers/identity_cache_spec.rb
index 1acc4b826..b3292a963 100644
--- a/spec/tapioca/dsl/compilers/identity_cache_spec.rb
+++ b/spec/tapioca/dsl/compilers/identity_cache_spec.rb
@@ -102,10 +102,10 @@ def fetch_multi_by_blog_id(index_values, includes: nil); end
                     sig { params(index_values: T::Enumerable[T.untyped], includes: T.untyped).returns(T::Array[::Post]) }
                     def fetch_multi_by_title(index_values, includes: nil); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::Integer]]) }
                     def fetch_multi_id_by_blog_id(keys); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::Integer]]) }
                     def fetch_multi_id_by_title(keys); end
                   end
                 end
@@ -160,10 +160,10 @@ def fetch_multi_by_blog_id(index_values, includes: nil); end
                     sig { params(index_values: T::Enumerable[T.untyped], includes: T.untyped).returns(T::Array[::Post]) }
                     def fetch_multi_by_title(index_values, includes: nil); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::Integer]]) }
                     def fetch_multi_id_by_blog_id(keys); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T.nilable(::Integer)]) }
                     def fetch_multi_id_by_title(keys); end
                   end
                 end
@@ -205,7 +205,7 @@ def fetch_id_by_blog_id_and_title(blog_id, title); end
                     sig { params(index_values: T::Enumerable[T.untyped], includes: T.untyped).returns(T::Array[::Post]) }
                     def fetch_multi_by_blog_id_and_title(index_values, includes: nil); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::Integer]]) }
                     def fetch_multi_id_by_blog_id_and_title(keys); end
                   end
                 end
@@ -260,10 +260,10 @@ def fetch_multi_by_title(index_values, includes: nil); end
                     sig { params(index_values: T::Enumerable[T.untyped], includes: T.untyped).returns(T::Array[::Post]) }
                     def fetch_multi_by_title_and_review_date(index_values, includes: nil); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::Integer]]) }
                     def fetch_multi_id_by_title(keys); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::Integer]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T.nilable(::Integer)]) }
                     def fetch_multi_id_by_title_and_review_date(keys); end
                   end
                 end
@@ -401,6 +401,7 @@ def fetch_user; end
                   ActiveRecord::Schema.define do
                     create_table :posts do |t|
                       t.string :author
+                      t.string :name
                     end
                   end
                 end
@@ -412,6 +413,7 @@ class Post < ActiveRecord::Base
 
                   cache_attribute :author, by: :id
                   cache_attribute :author, by: [:id, :author]
+                  cache_attribute :name, by: :author, unique: false
                 end
               RUBY
 
@@ -426,11 +428,53 @@ def fetch_author_by_id(id); end
                     sig { params(id: T.untyped, author: T.untyped).returns(T.nilable(::String)) }
                     def fetch_author_by_id_and_author(id, author); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::String]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T.nilable(::String)]) }
                     def fetch_multi_author_by_id(keys); end
 
-                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Array[::String]) }
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T.nilable(::String)]) }
                     def fetch_multi_author_by_id_and_author(keys); end
+
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T::Array[::T.nilable(::String)]]) }
+                    def fetch_multi_name_by_author(keys); end
+
+                    sig { params(author: T.untyped).returns(T::Array[::T.nilable(::String)]) }
+                    def fetch_name_by_author(author); end
+                  end
+                end
+              RBI
+
+              assert_equal(expected, rbi_for(:Post))
+            end
+
+            it "allows missing unique cache attributes for non-nullable columns" do
+              add_ruby_file("schema.rb", <<~RUBY)
+                ActiveRecord::Migration.suppress_messages do
+                  ActiveRecord::Schema.define do
+                    create_table :posts do |t|
+                      t.string :author, null: false
+                    end
+                  end
+                end
+              RUBY
+
+              add_ruby_file("post.rb", <<~RUBY)
+                class Post < ActiveRecord::Base
+                  include IdentityCache
+
+                  cache_attribute :author, by: :id
+                end
+              RUBY
+
+              expected = <<~RBI
+                # typed: strong
+
+                class Post
+                  class << self
+                    sig { params(id: T.untyped).returns(T.nilable(::String)) }
+                    def fetch_author_by_id(id); end
+
+                    sig { params(keys: T::Enumerable[T.untyped]).returns(T::Hash[T.untyped, T.nilable(::String)]) }
+                    def fetch_multi_author_by_id(keys); end
                   end
                 end
               RBI