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[SMS]

Hi,

We are in a process of identifying the tables which are approaching the 4GB tablespace and expand them to 8GB.

To determine the tables to expand, I've been given the below formula

X = ( Row count * Row size * compression factor / Partition range )

1) Please clarify whether Row size is the same as the record length. If not in which db2 catalog or DB2 admin menu I can find this information for a table. Also where I can check for the compression factor.

2) After finding X, if it's close to 4GB / 16 mark (if num of partitions is 16) then can that table be considered for expansion ?

Can anyone guide me on this ?

Thanks & Regards,
SMS

[kolusu]

SMS,

Before we get to the specifics of creating a formula for compression, use stand-alone utility DSN1COMP to find out how much space it will save and how much processing it will require to compress your data. Run DSN1COMP on a data set that contains a table space, a table space partition, or an image copy. DSN1COMP generates a report of compression statistics but does not compress the data. For instructions on using DSN1COMP, check this link.

http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DSNUGJ12/3.7?DT=20050323210436

Hope this helps...

Cheers

Kolusu
_________________
Kolusu
www.linkedin.com/in/kolusu

[SMS]

Hi Kolusu,

Thanks for the information.

Actually I need to find out the tables which are approaching the 4GB mark
and take those tables for expanding the tablespace from 4 to 8GB.

The formula given below is to determine the tables to expand.This is not for data compression.

With that formula I'm not sure about the row size and where to look about the compression factor. Could you please help me out on this ?

Thanks,
SMS
_________________
Regards,
SMS

[videlord]

Where did you get the formula? This is not the best one for calculation of the space/disk storage usage. Reference 2.6 if Administration Guide for the calculation.

Try to answer your question:
1) Row size - get the value from AVGROWLEN from catalog table SYSIBM.SYSTABLE or SYSIBM.SYSTABLEPART after RUNSTATS
Compression factor is not needed for currunt existing data. It's already included in the AVGROWLEN

2) The data in each partition may not be the same, devided by partition number is not a good choice
There are some options of 4GB limitation, e.g.
- using compression if data is not compressed
- adding more partitions
- and clean unused data