What an Idea pragrammatic.... Nearly from three days struggling with this. Finally I solved it. Working great. Thank you very much. And I want to ask you one more thing. As already told I have three (Postpaid, Prepaid, Delivery) files for every 10 minutes. After calculating I am uploading all the values into DB like this.

   Date      Hour    Mo_resp  MT_resp     AO_resp     Percentage
10-08-2015   00:00    256       382          36          87%
10-08-2015   00:10    491       438          12          92%
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(Its a sample. Actually my DB contains 38 columns) Like this I am uploading all values for every 10 minutes. Now my requirement is to add all MO_resp all AO_resp ... and son on (all columns) which occurred in 00 hour to write an hourly report in excel sheet. For that I am Doing

 
use DBI;
my $hour_db = DBI->connect("DBI:mysql:database=$db;host=$host;mysql_so
+cket=/opt/lampstack-5.5.27-0/mysql/tmp/mysql.sock","root","", {'Raise
+Error' => 1});
my @column_names = ("MO_resp","MT_resp","AO_resp");
foreach my $column_name (@column_names)
{
    my $hour_sth = $hour_db->prepare("Select sum($column_name) from $t
+able_name where Date='$db_date' and Hour like='$hour:%'");
    $hour_sth->execute() or die $DBI::errstr;
    .....    
}
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#Like this I am reading each column sum one by one. But I feel this is not a good method. Can you show me a way???

As a side note, please be aware of SQL_Injection, you have had this pointed out to you a couple of times (Re^4: Problem passing date to SQL, Re^3: After parsing .xls the rows getting emerged). The DBI documentation has a section on using placeholders, the links you've been given previously have further examples.

First, I have to second marto in that you should always use placeholders, third (since second is already used) you could aggregate all your columns into one call:

my @column_names = ("MO_resp","MT_resp","AO_resp");
my $sql = "select ".join ",", map { "sum($_)" } @column_names;
$sql .= " from ? where Date = ? and Hour like ?";
my $hour_sth = $hour_db->prepare( $sql );

$hour_sth->execute($table_name, $db_date, "$hour:%") or die $DBI::errs
+tr;
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See join and map.
If you are iterating over $db_date and $hour, you should keep the call to $hour_db->prepare outside those loops to reduce the overhead of binding placeholders in the SQL statement.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

Hey Programatic you are also doing the same but you are passing all the column names once by using join & map. Good thought. But in place holders If i place table name its showing a error.

DBD::mysql::st execute failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''CDR' where Date = '13-10-2015' and Hour like '00:%'' at line 1 at DB_Test.pl line 25.

So I replaced my '?' with table name. Then its working good. Even though I used your logic I need to maintain all my column names in array. I want to change that. Here I am writing all columns in program into big arrays which is looking odd. Can I get that coloumn names from db???

Sample (Tested)

#!/usr/bin/perl
use strict;
use warnings;

use DBI;
my $db_date=$ARGV[0]; #04-10-2015

my $hour = "00";
my $db_name   = "ravi";
my $table_name = "CDR";
my $host      = "xxx.xx.x.xxx";

my @CDR_array = ("Total_MO","Total_MO_sucess","MO_userdep_error","MO_s
+ubcrib_error","MO_system_error","Total_MO_success_rate","Total_AO","T
+otal_AO_sucess","AO_userdep_error","AO_subcrib_error","AO_system_erro
+r","Total_AO_success_rate","Total_MT_P2P","Total_MT_sucess_P2P","MT_P
+2P_userdep_error","MT_P2P_subcrib_error","MT_P2P_system_error","Total
+_MT_P2P_success_rate","Total_MT_A2P","Total_MT_sucess_A2P","MT_A2P_us
+erdep_error","MT_A2P_subcrib_error","MT_A2P_system_error","Total_MT_A
+2P_success_rate","Total_AT","Total_AT_sucess","AT_ESMEdep_error","AT_
+network_error","AT_system_error","Total_AT_success_rate","P2P_FDA_cou
+nt","P2P_FDA_success_count","P2P_FDA_success_rate","A2P_FDA_count","A
+2P_FDA_success_count","A2P_FDA_success_rate","Total_Count","Total_TPS
+","Greatest_TPS");

my $dbh = DBI->connect("DBI:mysql:database=$db_name;host=$host;mysql_s
+ocket=/opt/lampstack-5.5.27-0/mysql/tmp/mysql.sock","root","",{'Raise
+Error' => 1});

my $sql = "select ".join ",", map { "sum($_)" } @CDR_array;
$sql .= " from CDR where Date = ? and Hour like ?";

my $sth = $dbh->prepare( $sql ) or die "Cant get prepare";
$sth->execute($db_date, "$hour:%") or die $DBI::errstr;

my @my_array = $sth->fetchrow_array();

print $my_array[1],$/;
print @my_array,$/;
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plus you seem to have misunderstood the first sentence of this. "programmatic" is a quality of his nick, see e.g. there :-)

My nick feels honoured being linked to something as old as FORTRAN - but the concept is much older; it was invented after speech and before writing, and eventually led to an early cosmic calculator (though at that time writing already had been invented, I guess).

I have heard (through memory sharing) that australian aborigines still have a vast block of shared memory, which they access entirely wireless.

Before the concept of shmem, there was fork.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'