Named Pipe

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nshashi.85
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Named Pipe

Post by nshashi.85 »

I have a fastexport job.
when we are using datafile the following error was coming.
"Fatal: Cannot Open Datafile".

Then we ran the job using NamedPipe, which is successful.

what is the difference between the named pipe and data file?

any help?
SHASHI
chulett
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Post by chulett »

You can google up the definition of a 'named pipe' if that concept is unfamiliar to you. However, that shouldn't be the difference between success and failure here. :?

How about explaining your job design? Saying you have a "fastexport job" doesn't really tell us much of anything.
-craig

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ray.wurlod
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Post by ray.wurlod »

Au contraire, mon ami...

"FastExport" indicates extraction from Teradata. It may (for example) be that the user ID for Teradata lacks permission to create a file in the indicated directory but can create a fifo file (named pipe), presumably in a different directory.
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chulett
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Post by chulett »

ray.wurlod wrote:"FastExport" indicates extraction from Teradata.
Well, ok... doesn't tell us much other than that. :wink:
-craig

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ray.wurlod
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Post by ray.wurlod »

Is there any more information in the error entry in the DataStage job log? Is there any more information logged in the Teradata system?
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toshea
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Post by toshea »

With the named pipe option, the FastExport process will stream data to a named pipe, and the Teradata MultiLoad plug-in will concurrently read the data from that named pipe.

If you turn off the named pipe option, the MultiLoad plug-in will first run FastExport to dump the output to a sequential data file. Then it will read that sequential data file and send the data down the output link. This is slower than using a named pipe since you don't get the concurrency, but it is a workaround if you have named pipe issues. It is generally preferred to use named pipes if possible.
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