JB wrote:
> Sam Siegel schrieb:
>
>>Jerry Peters wrote:
>>
>>>j?rg brehe <Joerg.Brehe@[EMAIL PROTECTED]
> wrote:
>>>
>>>
>>>>Greg, thanks for for your explanations. Something of your comments
>
> I
>
>>>>have found out myself last day.
>>>>
>>>>It's not so easy for a beginner. On UNIX it's more simple, to get
>
> the
>
>>>>Offset in a file. I shall read the offset of the beginning and end
>
> of
>
>>>>Document X in a printfile. There are millions of documents in
>>>>printfiles.
>>>>
>>>>On HOST there is some trouble, because it's common to use
>>>>concatination. Normally we put this printfile in a big sort (for
>>>>example DFSORT, SYNCSORT e.t.c.) and hope the best.
>>>>
>>>>There is some hope that's faster to position to the right document,
>
> if
>
>>>>have read the position in a first read and put this
>>>>position,(TTR,Offset) in a smaller data set, and then use this
>>>>information to jump to the right position in data set X. The next
>>>>document is perhaps in another file and so on. I think, this will
>
> only
>
>>>>work in some cases. In most case the sort will be faster.
>>>>
>>>>The crux is, our product works on other plattforms, and there we
>
> need
>
>>>>a programm which can read the offset. Sort is on other plattforms
>
> not
>
>>>>so fast as on HOST. The Modul must have the same functions and
>>>>interfaces as on HOST, only it is written in C. On UNIX is no
>>>>concatination and FSEEK is what we need. It's easy.
>>>>
>>>>Now, the problem. Excp seems to be adequate to get all information
>
> of
>
>>>>the records on HOST.
>>>>IBM says: If I use EXCP and switch to another volume, i can use
>
> EOV.
>
>>>>To return to a previous volume I must close an reopen the data set.
>>>>This is slow.
>>>>
>>>>I have tried to use BDAM with EXCP. BDAM does not sup****t
>>>>concatination. I need one BDAM DCB for each DD. So, I search for
>>>>another Macro and found RDJFCB. IBM gives an example for doing this
>
> on
>
>>>>one volume. If I use EXCP with BDAM the position is TTTR, not TTR,
>>>>that's a little difference.
>>>>BDAM gives access to all volumes at the same time, and there is no
>>>>need of EOV. The position on a volume is MBBCCHHR, M is the
>
> extension.
>
>>>>I have try to use EXCP with concatinated data sets. It doesn't
>
> work.
>
>>>
>>>AFAIK excp works for concatenations, IIRC you need to call EOV at
>
> the
>
>>>end of each dataset to switch to the next one.
>>>
>>>Try BSAM using note/point and use dynalloc (svc99) to allocate each
>>>dataset, BSAM's a heck of alot simpler to use than EXCP. Also if
>
> the
>
>>>dataset gets moved your saved ttr's will still be valid. You'll
>
> need
>
>>>to save the DSN along with the ttr for each document, but since
>
> DSN's
>
>>>are at most 44 bytes this shouldn't be too bad. Sort though may
>
> still
>
>>>be the fastest way, I've sorted some humongous files in relatively
>>>litle time.
>>
>>I agree with Jerry about using BSAM along with NOTE/POINT macros.
>
> You
>
>>can easily index the contents of your datasets and then retrieve the
>>information very rapidly. One thing to remember is that each
>
> individual
>
>>datasets in the concatentation can span volumes. Therefore it is
>>im****ant to record the relative volume for each dataset along with
>
> the
>
>>NOTE/POINT information as the NOTE/POINT information is relative to a
>
>
>>specific volume. The relative volume can be tracked by using an EOV
>>exit. Then when you open the dataset for idata retrieveal you can
>
> use
>
>>RDJFCB and open TYPE=J to skip to the correct volume. This works for
>
>
>>both disk and tape. For tape it is very effeicent because no mount
>
> will
>
>>be attempted for any of the skipped volumes.
>
>
>
> I have written for a half year a programm which uses BSAM and use note
> and point. The concatenation was one of the problems. The other problem
> are the volumes. therefore I have tried to code an EXCP program with
> BDAM
>
> RECIN DCB DSORG=DA,MACRF=RIC,OPTCD=R,EODAD=DATAEND
>
> with one open I should get all volumes. Here was the problem, that I
> only get all records of the first track I point. I have written this in
> another message in this group. No response. I' am following some Ideas
> of Gilbert St. Flour cbt 183. I increment the track number, and in
> the next track I get only the first record of the last track. If I
> position in the beginning to Track Number 3 for example, I get the
> whole track 3, and the deblocking gives me all records on this track.
> The next increment to track 4 gives only the first record of the last
> track. If I use only EXCP without BDAM
>
> RECIN DCB DSORG=PO,MACRF=(E),EODAD=DATAEND
>
> all went well. I do not understand, why.
>
> The problem above is I think, I can only go forward through the files
> with EOV. To Position on the beginning I need need a reopen. Or is
> there a better way to manage this.
>
>
>
>
>>>>regards
>>>>J?rg
>
>
I need to restore some code that does most of this type of processing.
It may take a few days to find it.
Regards,
Sam
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