Re: newbie index question

Correct.

If any column in the index is NOT NULL, then every row in the table must appear in the index, so your count(*) from table will tell you how many rows are in the index. In fact, in this case, recent versions of Oracle have the option for doing a FAST FULL SCAN on the index in order to count the rows in the table.

--
Jonathan Lewis
Yet another Oracle-related web site:  http://www.jlcomp.demon.co.uk

Practical Oracle 8i:  Building Efficient Databases
Publishers:  Addison-Wesley

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Phillip wrote in message <3A8B0E1E.F2B02F22_at_wholefoods.com>...


>If I have an index on multiple columns, one of which is has a not null

>constraint, can I find out how many rows are in the index by simply

>doing a select count(*) on the table?  My thinking is that since the

>column doesn't allow nulls, finding out how many rows in the table will

>tell me how many rows are in the index.  Please advise...

>

>--

>Phillip

>