Re: How to calculate the size of an index?

From: Sybrand Bakker <gooiditweg_at_sybrandb.demon.nl>
Date: Tue, 13 Jan 2004 08:53:04 +0100
Message-ID: <dj4700teh6663eh6ihj4km5dlekuepgdad@4ax.com>

On 12 Jan 2004 19:23:47 -0800, jeffyee_at_hotmail.com (Jeffrey Yee) wrote:

>The reason I don't use dba_segments because it tells me how much space
>has been allocated, but not the actual space used.

You can be pretty sure almost all of it is used. Otherwise use the dbms_space package (sample code in Appendix A on 'Expert One on One' by Thomas Kyte) to check out how much of it is really used

>
>Therefore, can you please advice if I can rely on the num_rows *
>avg_row_len to calcualte the size of the tables?

Likely it will be way off. The only way to know for sure is to ANALYZE the affected objects.

--
Sybrand Bakker, Senior Oracle DBA

Received on Tue Jan 13 2004 - 01:53:04 CST