this had better be a detail set, or you're simply out of luck.  further, if
it's an existing database and you don't already have the dummy item, ditto.
then,

Option 1: provided that you've never deleted a record, yes, the records will
appear in the order they were added.  Your performance should be
approximately that of reading a plain flat sequential file with a tiny
amount of Image overhead.  If you've ever deleted records, new records will
fill their holes, so option 1 is out.  If no deletions and you want super
performance, use Suprtool, which bypasses not just Image but the file
system, so you get huge blocks of recs for each read.

Option 2: assuming an always-existent path, each record on each chain (each
chain occuring, separately with every possible value in the path's item) on
that path will be returned in entry sequence, deletions or not.  So you'll
be able to see the relative sequence of entry for each path-item value, but
for different values, no dice.

If this is for a NEW database, your dummy item trick will work fine, but be
sure to put it at the end of the record - sort items AND EVERYTHING TO THEIR
RIGHT are included in the 'sort'.  You can use this trick to keep a detail
set in 'key' sequence, too - put the dummy field at the front, and the key
field next.

Creating a new path on an existing base is not going to help.



> -----Original Message-----
> From: Venkatraman Ramakrishnan [mailto:[log in to unmask]]
> Sent: Friday, September 24, 2004 10:09 AM
> To: [log in to unmask]
> Subject: Turbo Image Help
>
>
> Hello Everybody,
>
> We are writing HP Cobol programs to access Turbo IMAGE
> databases in MPE
>
> We want to retrieve the records in the sequence in which they were
> inserted into the dataset. We have thought of the below three options
>
> Option 1: Serial read using DBGET Mode 2
>
> a) Serial read the dataset using DBGET Mode 2
> b) Process each record
>
> Question:
> 1. Will be the sequence in this case be maintained?
> 2. Will there be performance issues when the dataset size is
> going to be
> huge as DBGET Mode 2 needs to pass through each record
>
> Option 2: Chain read using DBGET Mode 5
>
> a) Chain read using a dummy field created which will select all the
> records in the dataset
> b) Sort the table using a Sequence based on the above dummy field
> c) Process each record
>
> Option 3: Message file (Option not preferred)
>
> a) Insert records into message file
> b) Read from message file and process the record
>
> Pls. let us know your thoughts on the feasibility of first two options
> and which would be preferable and why. We have decided not to use
> message files for the same.
>
>
> Warm Regards
> Venkat=20
>
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