Newbie question on table design.

Hi,

I have a table T with -- let's say -- a million+ records. The
application allows logical deletion of a small fraction of these
records. (Un-deletion of deleted records is allowed if you have admin
privs via a Priveleges table.)

I can easily think of 2 ways to support record un-/deletion.

1. Add an 'is_deleted' column that can take a binary 1/0 value (1 =
deleted, 0 = not-deleted).

This approach will result in...
+ simplest possible SQL;
- more space overhead (for at least some if not all DBMSes, now or
in future) due
to addition of a full column for a million+ rows most of which
will
anyway hold a single value (namely, 0 = not-deleted).

2. Alternatively, create another Deleted_T table in which the records
deleted from T would be inserted.

This approach will result in...
- slightly more involved SQL;
+ far less space overhead as only very rare, exception information
ends up getting recorded.

Presently, I tend to like #2 because...
* I can live with the 'slightly more involved SQL';
* I can live with the small speed overhead of consulting an
additional table (Deleted_T);
* I welcome every bit of free disk space on by server.

I cannot foresee any other de/merits entailing these approaches. If
you can, would you please point them out and/or recommend me your
favorite.

Thanks.
A DBMS newbie.

.

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