Re: count(*) v. count(pk)

>1) Is this in fact true (that a count(*) always does a full table scan)?
**** Yes count(*) always does a FTS

>2) Isn't counting on the primary key an impossibility if the key is
comprised
>of multiple columns?

• No. You can do SELECT COUNT(ename||empno) from emp;

>3) Can anyone suggest any other method for quickly retieving total rows
from
>large, multi-column-PK tables?

• If you keep your statistics upto-date a simple solution would be query the dba_tables to see the number of rows. Analyze your tables and then query the num_rows column of dba_tables.

HTH
Venkat Received on Mon Apr 27 1998 - 14:16:52 CDT