Re: File size with varlen fields

[Vern Hamberg <vhamberg@xxxxxxxxxxx>]

 Albert

This sounds like it thinks the fields are the full length, even though 
you have shorter values. Take a look with DSPPFM, then press F10 and 
F11. You'll get and over/under hex display. See what the first 2 bytes 
are for the varlen field. That gives the length it thinks you have.

VARLEN fields can be tricky - if you fill them from fixed-length 
variables, it takes the full length of the variable, so it includes 
trailing blanks. In ILE RPG you need to use at least a %trimr() function.

You might try an update - make a test table with CPYF by selecting maybe 
the first 25 records. See what the file size is. Then do an SQL UPDATE 
along the lines of

update table set varfield = strip(varfield)

Then see what the size is. You might need to do a RGZPFM to recover the 
space used for the full-length values, I thought that at one time the 
auxiliary space was not recovered until a reorganize.

Or do a DSPFFD and see what the allocated length is - be sure it's not 
the full length of the field. For best compromise of performance and 
disk utilization, it should be a length that takes in about 80-90% of 
the records.

Maybe!!!
Vern

On 9/14/2010 6:03 PM, Albert York wrote:
> I have a very long field (32000 bytes) that I defined in a file using
> varlen. Most of the time the field will be around 1 K but sometimes it
> could be 32000 bytes.
>
> When I look at the file size it shows 1.357 GB for 44180 records. When
> I look at the records the field size for that field looks correct.
>
> Why is the file so large?
>
> Thanks,
>
> Albert