RE: How accurate is ALL_INDEXES.NUM_ROWS for the PK index?

I think the absence of the asterisk is a documentation error - note that the sample_size and last_analyzed are also not marked as being dependent on analyze or gather_stats !


Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
_at_jloracle

________________________________________
From: oracle-l-bounce_at_freelists.org [oracle-l-bounce@freelists.org] on behalf of Thomas Kellerer [thomas.kellerer@mgm-tp.com]
Sent: 16 January 2015 08:41
To: oracle-l_at_freelists.org
Subject: How accurate is ALL_INDEXES.NUM_ROWS for the PK index?

Hello list,

as a means to get a quick overview on how many rows each table has, I wonder how accurate the NUM_ROWS column in ALL_INDEXES actually is for the primary key index (or a UNIQUE index on a NOT NULL column).

Unlike other columns in that view (and e.g. the NUM_ROWS column in ALL_TABLES) it is not marked as being dependent on gathering statistics.

So: when does Oracle update that information and how accurate is it?

Does it reflect the number of rows in "near real-time" (within the rules of transactional visibility of course), or is it just as "unreliable" as ALL_TABLES.NUM_ROWS?

Regards
Thomas
--
http://www.freelists.org/webpage/oracle-l


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