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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:
 

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flow-merge(1)						      General Commands Manual						     flow-merge(1)

NAME
flow-merge -- Merge flow files. SYNOPSIS
flow-merge [-aghm] [-b big|little] [-C comment] [-d debug_level] [-o filename] [-z z_level] [file|directory ...] DESCRIPTION
The flow-merge utility processes files and/or directories of files in the flow-tools format. The resulting merged data set is written to the standard output or file specified by -o. If file is a single dash (`-') or absent, flow-merge will read from the standard input. Unlike flow-cat, flow-merge interleaves flow records preserving the relative chronological order. OPTIONS
-a Do not ignore filenames that begin with tmp. -b big|little Byte order of output. -C Comment Add a comment. -d debug_level Enable debugging. -g Sort file list by capture start time before processing. -h Display help. -m Disable the use of mmap(). -p Preload headers. Use to preserve meta information such as lost flows. -o file Write to file instead of the standard out. -z z_level Configure compression level to z_level. 0 is disabled (no compression), 9 is highest compression. file|directory... Process the files and/or directory. EXAMPLES
Merge all flow files begining with ft-v05.2001-05.01, use flow-print to display the results. flow-merge ft-v05.2001-05-01.* | flow-print BUGS
None known. AUTHOR
Larry Lidz ellidz@eridu.uchicago.edu SEE ALSO
flow-tools(1) flow-merge(1)
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