vijay.db@gmail.com wrote:
> Hi Group,
>
> It's really confusing to calculate the size of the DB2 UDB database in
> versions lesser than 8.2.
>
> In Version 8.2 if we run the query db2 "call get_dbsize_info(?,?,?,0)"
> it gives us an approximate size of the database.
>
> But it we try calculating the file system sizes of the database home
> directory, containers file system it gives some other size...
>
> it's so confusing which database size is accurate. Do we have stick to
> the size given by DB2 or size w.r.t the OS file systems.
>
> Where as in versions say like 8.1 0r Version 7, the above procedure is
> not working. So is there any other alternate method to calculate the
> size of the database?
>
> And for the group's information, I got a query which is also giving
> the size of the database, this I got while searching for my query in
> Google. the query is:
>
> db2 connect to <dbname>
>
> db2 "select (SUM(total_pages)*4)/(1024.0*1024)
> TOTAL_ALLOCATED_SPACE_IN_GB from table
> (snapshot_tbs_cfg('<dbname>',-1)) TBS_SPCE"
>
> db2 connect reset.
>
> Whether the above query is accurate in calculating the database size?
>
> Also I got a few doubt reg above query? what does this mean
> (SUM(total_pages)*4
> think it works for tablespaces with default 4KB page size, what
> happens if the tablespaces are with different page sizes say some
> tablespaces in 4K and some tablespaces in 8/16/32K. So this case how
> should we calculate the size of the above database using the above
> query.
>
> If there is any other method to calculate the database size, pls
> kindly let me know. As the need is urgent, kindly let me know if you
> know the solution for my problem.
>
> Thanks in Advance.
> vj_dba
>

I have always used the size of a backup image to get a close
approximation of "how big" a database is....