optimization: prefer relation.none over relation.where("false")

Using `relation.none` instead of `relation.where("false")` avoids an sql query.

app/logical/post_sets/artist.rb

@@ -14,7 +14,7 @@ module PostSets
         query
       end
     rescue ::Post::SearchError
-      ::Post.where("false")
+      ::Post.none
     end
 
     def presenter

app/models/comment.rb

@@ -64,7 +64,7 @@ class Comment < ApplicationRecord
     end
 
     def for_creator(user_id)
-      user_id.present? ? where("creator_id = ?", user_id) : where("false")
+      user_id.present? ? where("creator_id = ?", user_id) : none
     end
 
     def for_creator_name(user_name)

app/models/post_archive.rb

@@ -22,7 +22,7 @@ class PostArchive < ApplicationRecord
       if user_id
         where("updater_id = ?", user_id)
       else
-        where("false")
+        none
       end
     end
 

app/models/post_flag.rb

@@ -76,7 +76,7 @@ class PostFlag < ApplicationRecord
           q = q.where.not(post_id: CurrentUser.user.posts)
           q = q.where("creator_id = ?", params[:creator_id].to_i)
         else
-          q = q.where("false")
+          q = q.none
         end
       end
 
@@ -86,7 +86,7 @@ class PostFlag < ApplicationRecord
           q = q.where.not(post_id: CurrentUser.user.posts)
           q = q.where("creator_id = ?", flagger_id)
         else
-          q = q.where("false")
+          q = q.none
         end
       end