06-29-2010
Quote:
Originally Posted by
radoulov
Thanks
radoulov for this note but could you be more precise or at least give an example.
9 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi,
I have a file with multiple records...and I have to select records based on first column....here is the sample file...
I01,abc,125,1a2,LBVI02
I01,abc,126,2b5,LBVI02
I02,20070530,254,abc,LLBI01
I02,20070820,111,bvd,NGBI01
I need all records with I01 in first field in one file and... (8 Replies)
Discussion started by: mgirinath
8 Replies
2. Shell Programming and Scripting
hi..
i need to optimize my select query ..
my situation is like this ..
i have 15 lac recors in my table..
the following query takes nine seconds to give the required output..
SELECT max(ah.AUC_AMT),
SUBSTRING_INDEX(GROUP_CONCAT(SUBSTRING_INDEX(ah.AUC_CUS_NAME,'@',1) order by AUC_AMT... (0 Replies)
Discussion started by: senkerth
0 Replies
3. UNIX for Advanced & Expert Users
hi..
i need to optimize my select query ..
my situation is like this ..
i have 15 lac recors in my table..
the following query takes nine seconds to give the required output..
SELECT max(ah.AUC_AMT),
SUBSTRING_INDEX(GROUP_CONCAT(SUBSTRING_INDEX(ah.AUC_CUS_NAME,'@',1) order by AUC_AMT... (1 Reply)
Discussion started by: senkerth
1 Replies
4. UNIX for Dummies Questions & Answers
Hi, I would just like to know how to get the file with the max filename on a directory and get rid of all the others. For example, in directory A:/ i have the ff files:
APPLE2001
APPLE2002
APPLE2003
GRAPE2004
what I want to get is the max in files whose filenames start with APPLE*,... (4 Replies)
Discussion started by: madden
4 Replies
5. Shell Programming and Scripting
I have a file with 3 columns
I want to get the record with the max salary. If there are more than 1 record having the highest salary, i want any one of them.
empid,ename,Sal
1,abc,100
2,def,200
3,xyz,300
4,pqr,100
5,mnq,300
Output
Any record with 300 as salary
Please use next... (1 Reply)
Discussion started by: traininfa
1 Replies
6. Programming
I feel stupid for asking this because it seems that MYSQL code isn't working the way that I think it should work.
Basically I wrote code like this:
select * from `Test_DC_Trailer` HAVING max(DR_RefKey);
Where the DR_RefKey is a unique numeric field that is auto iterated (like a primary key)... (7 Replies)
Discussion started by: Astrocloud
7 Replies
7. Shell Programming and Scripting
I want records which have more than one and different value in the second column on the below sample file.
Ex, I have the samle file below :-
XYZ 1
XYZ 3
abc 1
abc 1
qwe 2
qwe 1
qwe 3
I want to select XYZ and QWE line only. (6 Replies)
Discussion started by: Sanjeev Yadav
6 Replies
8. Programming
Dear community,
I woul like to make a query to output all the users having the same IP address.
The table is somethig like:
name logged_ip
==== =========
user1 127.0.0.1
user2 127.0.0.2
user3 127.0.0.3
user4 127.0.0.1
user5 127.0.0.2
user6 127.0.0.5I used this query... (4 Replies)
Discussion started by: Lord Spectre
4 Replies
9. Shell Programming and Scripting
Hello,
I am working on an application that uses allot of memory depending on the input. I am also working on more than one processing algorithm.
The program has a long processing time (hours) so it would be nice to be able to monitor the maximum memory footprint of the application during runs... (1 Reply)
Discussion started by: LMHmedchem
1 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)
NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$SHELL -c". This doesn't work as intended:
ssh host touch 'hi there' # fails
It creates 2 files, hi and there. Instead, do this:
cmd=`shell-quote touch 'hi there'`
ssh host "$cmd"
This gives you just 1 file, hi there.
process find output
It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to
split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote:
eval set -- `find -type f -print0 | xargs -0 shell-quote --`
debug shell scripts
shell-quote is better than echo for debugging shell scripts.
debug() {
[ -z "$debug" ] || shell-quote "debug:" "$@"
}
With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can.
save a command for later
shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command
you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are
things the user can't pass through), you can do something like this:
user_switches=
while [ $# != 0 ]
do
case x$1 in
x--pass-through)
[ $# -gt 1 ] || die "need an argument for $1"
user_switches="$user_switches "`shell-quote -- "$2"`
shift;;
# process other switches
esac
shift
done
# later
eval "shell-quote some-command $user_switches my args"
OPTIONS
--debug
Turn debugging on.
--help
Show the usage message and die.
--version
Show the version number and exit.
AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions.
AUTHOR
Roderick Schertler <roderick@argon.org>
perl v5.16.3 2010-06-11 SHELL-QUOTE(1)