scratch disk Q

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just4u_sharath
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scratch disk Q

Post by just4u_sharath »

i learnt that scratch disk has filesystems for temporary storage and resource disk has filesystems for permament storage. But i cannot understand difference between permanent and temporary. whenever we run a job all the data generated between source and target is temporary data. Now where is the point of permanent data on datastage.
how the resource disk and scratch disk is used?
I know for sorting we generally used scratch disk, and for what other operations this scratch disk is used? for what operaions resource disk is used?
ray.wurlod
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Post by ray.wurlod »

Simply, "permanent storage" means the data files of Data Sets, File Sets and Lookup File Sets. "Temporary storage" covers files created during (and removed after) certain processing, such as sorting. Any operator that needs more memory than it has been allocated will create temporary files on the scratch disk. By default - unless you specify a different location - some bulk loader "log" and "bad" files are also written to the scratch disk.
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keshav0307
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Post by keshav0307 »

In datastage permanent and temporary. is like your hard disk and RAM memory in PC/laptop.
Resource disk is like the Temp directory in your PC, which is used to store some files temporarily but is in the hard disk(permanent Storage).
Calculation/processing is done in RAM (the temporary storage).
Reource disk is generally used in storing the datafiles of a dataset.
temprary files for some stages(like MLOAD), and may be many more..
sunayan_pal
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Post by sunayan_pal »

ray.wurlod wrote:Simply, "permanent storage" means the data files of Data Sets, File Sets and Lookup File Sets. "Temporary storage" covers files created during (and removed after) certain processing, such as sorting. ...
let say in case of sorting and remove duplicate stage the intermediate/temporary data will be there in the RAM and then if needed in the drive ( scratch disc )
please correct if i am wrong.
regards
sunayan
ray.wurlod
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Post by ray.wurlod »

As a general rule you are correct.
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