[erlang-questions] Transform mnesia table into new table

[Ryan Brown]

I have an escript that I can run to update the data in an existing mnesia
table:

#!/usr/bin/env escript

%% -*- erlang -*-


-include("record_defs.hrl").


main([NodeIn|_]) ->

        Node = list_to_atom(NodeIn),

        ok = migrate_record_schema(Node),

        halt().



migrate_record_schema(Node) ->

        MigrationFun = fun({

                                old_record,

                                Id,

                                Name,

                                DateCreated,

                                DateDeactivated,

                                Password,

                                Url

                        }) ->

                                {

                                new_record,

                                Id,

                                Name,

                                DateCreated,

                                DateDeactivated,

                                Password,

                                Url,

                                false

                                }

                        end,

        {atomic, ok} = rpc:call(Node, mnesia, transform_table, [old_record,
MigrationFun, record_info(fields, new_record)]),

  ok.
The problem I have is that when I deploy the code that uses this new record
schema and update the schema, this new transformed data gets replicated to
the other clustered nodes as well.

So, what I was hoping to do was create a new table say new_record, that I
place the transformed records into. The new code will reference that table.
The yet-to-be-upgraded nodes will still continue to reference the old
schema until they get the new code deployed.

Is this possible without jumping through major hoops? Or, maybe I'm missing
a simpler solution?

Any help would be greatly appreciated.
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