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Full Discussion: Need help for faster file read and grep in big files
Top Forums UNIX for Advanced & Expert Users Need help for faster file read and grep in big files Post 303018517 by Corona688 on Friday 8th of June 2018 03:33:59 PM
Old 06-08-2018
Guessing you're running grep once per record, if it's taking hours. How about:

Code:
$ awk 'LFN != FILENAME { LFN = FILENAME ; FILENUM++ }
FILENUM==1 { A[$1] ; next }
FILENUM==2 { if($4 in A)        S1[$6] = $4 ; next }
FILENUM==3 { if($4 in S1) print S1[$4], $4, $6 }' \
        FS="[ |]+" inputFile1.txt inputFile2.txt inputFile3.txt

3434343 myout1 FinalOut1
3434343 myout2 FinalOut2
3434343 myout2 FinalOut3

$

One command.

If your real data's any different from what you posted it may need fine tuning.
This User Gave Thanks to Corona688 For This Post:
jim mcnamara
 

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SYNOPSIS

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DESCRIPTION

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OPTIONS

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	      look up STRING in all indices of all manuals.

       -d, --directory=DIR
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       For a summary of key bindings, type h within Info.

EXAMPLES

       info   show top-level dir menu

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	      show the general manual for Info readers

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       info emacs
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