Why we need datasets ratherthan sequential files?
Answers were Sorted based on User's Feedback
Answer / sagar
When you use sequential file as Source,at the time of
compilation it will convert to native format from
ASCII.where as,when you go for using datasets... conversion
is not required.Also, by default sequenctila files we be
processed in sequenc only.sequential files can accommodate
up to 2GB only.sequentila files does not support NULL
values....all the above can me overcome using dataset
stage....but selection is depeneds on the
requirement....suppose if you want to capture rejected
data....in that case you need to use sequential file or
fileset stage....
| Is This Answer Correct ? | 22 Yes | 4 No |
Answer / kiran
First we Know about Seq file and Dataset.
Seg file is used Extract the from flatfiles and load into
flatfiles and limit is 2GB
Dataset is a intermidiate stage and it has paralism when
load data into dataset and it inprove the performanece.
| Is This Answer Correct ? | 22 Yes | 11 No |
Answer / chiranjeevi.a
To over come the limitation of sequential file,espesially
sequential file: By default reads and writes sequentially
>memory limit is up to 2GB
>conversion is needed
>sourse stores the data out side of datastage
Data file:
>parallel process
>memory is unlimited
>No conversion is needed while reading the data(its
basically in native format).
>stores data inside the repositary
| Is This Answer Correct ? | 11 Yes | 2 No |
Answer / narayana
file set is nothing but collection of sequential files. if sourse database is greater than 2 GB than prefer to use file set.
Data set is internal stage in datastage.the extension of data set is .ds it never used to extract data from client location .it is used as intermediate stage between two tables.
Sequential : 1)it supports all formats like txt,csv,xls,etc.
2)it is used to extract data from flat files from client location.
Data set:1)it supports only .ds format
2)it will never extract data from flat files from client location.
| Is This Answer Correct ? | 4 Yes | 2 No |
Answer / pavan
datasets get processed in our local system rather than at
the server so performance gets enhanced in this case as
server is not loaded.
| Is This Answer Correct ? | 0 Yes | 13 No |
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