begin_isolated_db_transaction

# File activerecord/lib/active_record/connection_adapters/sqlite3/database_statements.rb, line 81
        def begin_isolated_db_transaction(isolation) #:nodoc
          raise TransactionIsolationError, "SQLite3 only supports the `read_uncommitted` transaction isolation level" if isolation != :read_uncommitted
          raise StandardError, "You need to enable the shared-cache mode in SQLite mode before attempting to change the transaction isolation level" unless shared_cache?

          Thread.current.thread_variable_set("read_uncommitted", @connection.get_first_value("PRAGMA read_uncommitted"))
          @connection.read_uncommitted = true
          begin_db_transaction
        end