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Top Forums Shell Programming and Scripting How to Pick Random records from a large file Post 302341798 by ajithshankar@ho on Thursday 6th of August 2009 03:24:12 PM
Old 08-06-2009
Data How to Pick Random records from a large file

Hi,

I have a huge file say with 2000000 records. The file has 42 fields. I would like to pick randomly 1000 records from this huge file. Can anyone help me how to do this?
 

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ldns-walk(1)						      General Commands Manual						      ldns-walk(1)

NAME
ldns-walk - Retrieve the contents of a DNSSEC signed zone SYNOPSIS
ldns-walk [ OPTION ] ZONE DESCRIPTION
ldns-walk is used to retrieve the contents of a DNSSEC signed zone. It does this through NSEC-walking (following the chain of NSEC records) and 'guessing' the next non-existent owner name for each NSEC. Note that it might get stuck on some wildcard records when used through a caching forwarder. This problem can be circumvented by querying the authoritative nameserver directly (with the @ argument). Of course the nameserver that is used must be DNSSEC-aware. OPTIONS
-f Do a 'full' zone walk; by default, ldns-walk will only show the names, and types present at those names. If this option is given, all resource records will be printed. -s name Start the walk with this owner name. Useful when continuing the walk for a large zone. @ nameserver Send the queries to this nameserver. BUGS
The full zone walk function is not complete yet, it does not correctly print delegation records AUTHOR
Written by Jelte Jansen as an example for ldns usage. REPORTING BUGS
Report bugs to <ldns-team@nlnetlabs.nl>. COPYRIGHT
Copyright (C) 2005 NLnet Labs. This is free software. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR- POSE. 21 Nov 2005 ldns-walk(1)
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