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Full Discussion: Incredibly inefficient cat | grep script
Top Forums Shell Programming and Scripting Incredibly inefficient cat | grep script Post 302913045 by RudiC on Wednesday 13th of August 2014 01:01:48 PM
Old 08-13-2014
Normally,
Code:
grep -f accurate_list.csv  production_list.csv

would be ideally fitted for the job, but I'm afraid the sheer numbers will blast it.
How about using split to get to smaller accurate lists, or, if both files are sorted, even smaller production files, and give it a try?
 

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LEARN ABOUT X11R4

zgrep

ZGREP(1)                                                      General Commands Manual                                                     ZGREP(1)

NAME

       zgrep - search possibly compressed files for a regular expression

SYNOPSIS

       zgrep [ grep_options ] [ -e ] pattern filename...

DESCRIPTION

       Zgrep  invokes  grep  on  compressed  or  gzipped  files.   These  grep  options  will  cause  zgrep  to  terminate  with  an  error  code:
       (-[drRzZ]|--di*|--exc*|--inc*|--rec*|--nu*).  All other options specified are passed directly to grep.  If no file is specified,  then  the
       standard input is decompressed if necessary and fed to grep.  Otherwise the given files are uncompressed if necessary and fed to grep.

       If the GREP environment variable is set, zgrep uses it as the grep program to be invoked.

EXIT CODE

       2 - An option that is not supported was specified.

AUTHOR

       Charles Levert (charles@comm.polymtl.ca)

SEE ALSO

       grep(1), gzexe(1), gzip(1), zdiff(1), zforce(1), zmore(1), znew(1)

                                                                                                                                          ZGREP(1)
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