Re: When does ROWID change ?

Jenda Krynicky wrote:
>
> Is it safe to use a ROWID as a key for some table?
>
> I have a table that doesn't have any reasonable key
> (I'd have to use the "sum" of many keys as the key).
> Into another table I compute some data which should be tied to the rows in the first table.
> Many rows from Table2 to one in Table1, most rows in Table1 do not have anything in Table2.
>
> I thought it's safe to tie the tables using Table1.ROWID as the key. I thought the ROWID would change only if
> I deleted and recreated the rows in Table1, or if I copied the data over to a different server.
> Is this assumption correct? Does "Analyze table" change the ROWIDs?
>
> It seemed to work OK at first but I get some strange results now and want to make sure this is not the problem..
>
> Thanks, Jenda (CC: would be appreciated)
> http://Jenda.Krynicky.cz

A table which does not have a key is not in 3rd Normal form and therefore is not truely relational. That indicates poor design. I'd even doubt that performing an ANALYZE TABLE would result in anything useful in this case because you'd probably get better performance from a rule-based optimization rather that a cost-based optimization since "no key" = "no indexable column" in most cases.

Hint: Normalize your data. Received on Wed Nov 03 1999 - 08:35:31 CST