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From: "John Chiu" <johnymc@netscape.net>
Newsgroups: comp.databases.oracle.server,comp.databases.oracle.misc
Subject: Re: How to find the size of a table?
Date: Thu, 11 Nov 1999 20:03:41 -0500
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The formula for calculating storage space for a row =
              average row size (get from sys.dba_tables or
                                           select  avg(vsize(col1))+
avg(vsize(col2)) +.......... from your_table; )
           + number of columns
           + number of columns > 250 characters
           + 3 bytes of row header

HTH

John Chiu

> If you analyze the table the statistics in sys.dba_tables will give you
> the average row size.  If you really want to know for a specific row
> then I think you can estimate it by summing a vsize function for each
> column plus adding the row overhead which you will have to calculate
> based on the datatypes.  Sort of fixed row overhead of 3 + length bytes
> + sum(vsize(col1) + vsize(col2) etc...)
>
> I can not remember if the overhead information is in the Concepts or
> the DBA manual, but it is documented.
> > Thanks,
> > Daivd
> >
> --
> Mark D. Powell  -- The only advice that counts is the advice that
>  you follow so follow your own advice --
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.