Dave,
> A couple of months ago there was a thread on the number of records that can
>be stored in a file under older versions of Palm OS and I never saw a
>definitive answer.
As I recall the threads over the years:
- Prior to OS 3.5, the record index was a (signed) int, so the max was 32767
- In OS 3.5, types werre made more explicit and should have become UInt16
though a few APIs were inadvertently labeled Int16 instead. Among
those was DmSortPosition().
- In 4.x (4.1??) those were corrected and all are now UInt16
So the definitive answer depends on which OS versions you want to support. For
pre-OS 3.5, stay below 32767. For 3.5+, you can get up to 65535 provided you
write your own replacements for some of the APIs such as DmSortPosition. From
some 4.x version on, you may use up to 65535 records. In OS6+, the limits
should no longer be an issue.
>For my test ... there were 64,797 records in the file when I finished. I didn't
>find the upper limit to the number of records that could be loaded ...
Well, assuming you were on OS4.1+, you were 738 from the limit.
> Does anyone know if this situation is improved under OS 5?
OS6. However, in OS5 you have some devices with more storage memory making it
possible to store much larger SKU counts possible without using VFS routines and
a mem card based inventory. (Which is not all bad either; you can insert the
card into a PC to transfer the files quickly and not need to Hot Sync at all...)
> I'd also be interested in the file sizes for different retail applications.
The most I'm aware of that any of my customers use is around 55-60K SKUs, but
there may be more. However, I can easily support massively larger SKU counts on
devices with enough memory. The key is to not perform the unpacking but to
write your routines to locate the SKUs from within the packed records. This not
only saves the unpacking time but lets you easily handle 100K (or whatever) SKUs
regardless of OS version.
I pack literally hundreds of SKUs per PDB data record in my inventory databases,
and many thousands per record used as cross-reference indexes. (I have instant
lookup by SKU, barcode, description, etc.)
>Has anyone had any experience with a retailer
>like a Wal-Mart Super Center or a Lowes?
I don't have any retail accounts, so I can't tell you. I'd assume *much* higher
than 100K would be possible.
Doug
--
For information on using the Palm Developer Forums, or to unsubscribe, please see
http://www.palmos.com/dev/support/forums/
