diff --git a/db/migrate/20220322024216_add_bookmark_polymorphic_columns.rb b/db/migrate/20220322024216_add_bookmark_polymorphic_columns.rb
index ebf87f84d83..922d611d5f3 100644
--- a/db/migrate/20220322024216_add_bookmark_polymorphic_columns.rb
+++ b/db/migrate/20220322024216_add_bookmark_polymorphic_columns.rb
@@ -2,9 +2,16 @@
 
 class AddBookmarkPolymorphicColumns < ActiveRecord::Migration[6.1]
   def change
-    add_column :bookmarks, :bookmarkable_id, :integer
-    add_column :bookmarks, :bookmarkable_type, :string
+    if !column_exists?(:bookmarks, :bookmarkable_id)
+      add_column :bookmarks, :bookmarkable_id, :integer
+    end
 
-    add_index :bookmarks, [:user_id, :bookmarkable_type, :bookmarkable_id], name: "idx_bookmarks_user_polymorphic_unique", unique: true
+    if !column_exists?(:bookmarks, :bookmarkable_type)
+      add_column :bookmarks, :bookmarkable_type, :string
+    end
+
+    if !index_exists?(:bookmarks, [:user_id, :bookmarkable_type, :bookmarkable_id])
+      add_index :bookmarks, [:user_id, :bookmarkable_type, :bookmarkable_id], name: "idx_bookmarks_user_polymorphic_unique", unique: true
+    end
   end
 end