Allow `truncate` for SQLite3 adapter and add `rails db:seed:replant` (#34779)

* Add `ActiveRecord::Base.connection.truncate` for SQLite3 adapter.

SQLite doesn't support `TRUNCATE TABLE`, but SQLite3 adapter can support
`ActiveRecord::Base.connection.truncate` by using `DELETE FROM`.

`DELETE` without `WHERE` uses "The Truncate Optimization",
see https://www.sqlite.org/lang_delete.html.

* Add `rails db:seed:replant` that truncates database tables and loads the seeds

Closes #34765

1 files changed, 10 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb b/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
index a82cea80ca..cedbae6b7f 100644
--- a/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/sqlite_database_tasks.rb
@@ -33,6 +33,16 @@ module ActiveRecord
         create
       end
 
+      def truncate_tables(*table_names)
+        return if table_names.empty?
+
+        ActiveRecord::Base.connection.disable_referential_integrity do
+          table_names.each do |table_name|
+            ActiveRecord::Base.connection.truncate(table_name)
+          end
+        end
+      end
+
       def charset
         connection.encoding
       end