On Sep 6, 2008, at 2:50 AM, Scott Hess wrote: > On Fri, Sep 5, 2008 at 11:31 PM, jonwood <[EMAIL PROTECTED]> > wrote: >> I have a table where the primary key consists of two columns. I'm >> doing this >> because these two columns combined must be unique, while each >> column is not >> unique on its own. >> >> Because of the increased complexity of a dual-column primary key >> for some >> operations, I'd like to use ROWID. But the documentation states the >> ROWID >> can change at any time so I'm not sure what I can do safely. > > Do this: > > CREATE TABLE t ( > id INTEGER PRIMARY KEY, > a TEXT NOT NULL, > b INTEGER NOT NULL, > UNIQUE (a, b) > ); > > (a,b) will be just as unique as in the first case, but now you can use > id as a stable alias for rowid. There will be the same number of > btrees (one keyed by rowid/id for the table, one for the index on > a,b), and things should take the same amount of space (since id is an > alias for rowid, not a new column). > > As a bonus, if the implementation of SQLite changes, SQL itself won't, > so id will _still_ be a valid integer primary key, even if the > implementation detail of rowid changes.
I promise that INTEGER PRIMARY KEY will always be an alias for the rowid in SQLite. This will not change. > D. Richard Hipp [EMAIL PROTECTED] _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
