writes

Locking Tables with Rails ActiveRecord

If you wanted to lock a table for writes using ActiveRecord (this may come in handy for other things as well), it is possible. You can do so by accessing the connection.execute method available to the model itself.

Here's an example of Model.connection.execute

Model.connection.execute( "LOCK TABLES #{Model.table_name} WRITE" )
...
Model.connection.execute( "UNLOCK TABLES" )

However, there is a better way recommended (updated from comments) which is to make the actual models methods like this: