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Full Discussion: Quick way to select many records from a large file
Top Forums Shell Programming and Scripting Quick way to select many records from a large file Post 302942338 by sea on Monday 27th of April 2015 07:22:23 PM
Old 04-27-2015
Hello and welcome to the forum.

Please use code tags for code block examples, as required by the forum rules.

Not sure on the script, as i dont know csh or ksh.
In bash i'd do:
Code:
while read line;do
   awk -v key="$line" {/^key/} {print $0} records.txt
done<key.txt

Then execute it:
Code:
$SHELL pick_records.s > output.txt

Note that i find "pick_" quite irritating, since you dont pick (as in: select a single entry) anything of something, but run through everything (every line) found.

Half a million (or just 200'000) lines/entries do need their time to be done.
You could figure out a difference by adding time in front of executing the script.
Code:
time $SHELL pick-records.sh

Hope this helps (hth)
 

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LEARN ABOUT MOJAVE

locale::script5.18

Locale::Script(3pm)					 Perl Programmers Reference Guide				       Locale::Script(3pm)

NAME

       Locale::Script - standard codes for script identification

SYNOPSIS

	  use Locale::Script;

	  $script  = code2script('phnx');		      # 'Phoenician'
	  $code    = script2code('Phoenician'); 	      # 'Phnx'
	  $code    = script2code('Phoenician',
				 LOCALE_CODE_NUMERIC);	      # 115

	  @codes   = all_script_codes();
	  @scripts = all_script_names();

DESCRIPTION

       The "Locale::Script" module provides access to standards codes used for identifying scripts, such as those defined in ISO 15924.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 15924
       four-letter codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying scripts. A code set may be specified using either a name, or a constant
       that is automatically exported by this module.

       For example, the two are equivalent:

	  $script = code2script('phnx','alpha');
	  $script = code2script('phnx',LOCALE_SCRIPT_ALPHA);

       The codesets currently supported are:

       alpha, LOCALE_SCRIPT_ALPHA
	   This is a set of four-letter (capitalized) codes from ISO 15924 such as 'Phnx' for Phoenician.  It also includes additions to this set
	   included in the IANA language registry.

	   The Zxxx, Zyyy, and Zzzz codes are not used.

	   This is the default code set.

       num, LOCALE_SCRIPT_NUMERIC
	   This is a set of three-digit numeric codes from ISO 15924 such as 115 for Phoenician.

ROUTINES

       code2script ( CODE [,CODESET] )
       script2code ( NAME [,CODESET] )
       script_code2code ( CODE ,CODESET ,CODESET2 )
       all_script_codes ( [CODESET] )
       all_script_names ( [CODESET] )
       Locale::Script::rename_script  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Script::add_script  ( CODE ,NAME [,CODESET] )
       Locale::Script::delete_script  ( CODE [,CODESET] )
       Locale::Script::add_script_alias  ( NAME ,NEW_NAME )
       Locale::Script::delete_script_alias  ( NAME )
       Locale::Script::rename_script_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Script::add_script_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Script::delete_script_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.unicode.org/iso15924/
	   Home page for ISO 15924.

       http://www.iana.org/assignments/language-subtag-registry
	   The IANA language subtag registry.

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 1997-2001 Canon Research Centre Europe (CRE).
	  Copyright (c) 2001-2010 Neil Bowers
	  Copyright (c) 2010-2013 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.18.2							    2013-11-04						       Locale::Script(3pm)
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