Best practices for a high performance Perl program

http://makepp.sourceforge.net/1.50/perl_performance.html

Validating data types in PERL

Since perl data types are very typeless and depends upon where they are used. There are some situations, when this design is awkward.

To validate data types,

Data::Types module can be installed and used.

However if you dont want to install, here are few quickies:

- To Check

% An Integer, Use regex /^[+-]?\d+$/ and ofcourse, not matched ones are non-intger
% A Decimal, /^[+-]?(?:\d+(?:\.\d*)?|\.\d+)$/
% Whole number, /^\d+$/
% Float number, /^([+-]?)(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?$/
%

Python Advance books

A Good link for description of these books.

http://wiki.python.org/moin/AdvancedBooks

How to group UNIX Solaris, Linux commands

Simply group them in a small bracket and separate them by semi colon (;)

123-bash: (ls -1;pwd;cd /tmp/curl)

It will list the files in CWD first, print the directory you are in, cd to /tmp/curl

How to get user input in PERL

It's simple -

- The angle bracket operator to read from STDIN (see I/O operators in perlop)
- If entering 'Y' or 'N' - make sure to use 'chomp' to cut the new line character.
- @ARGV - the array that holds parameters from the command line (see perlvar)
- Getopt::Long or Getopt::Std - for more powerful handling of command line arguments
- uc - to uppercase an expression
- ucfirst - to uppercase the first letter of an expression

Later in your code, you can compare by using 'eq' or 'ne' or '==' or '!=' or
pattern matching =~ m///, thingy to move on to do what you want.....

Solaris Kernel Modules operations

Kernel Modules:
---------------

modinfo : prints out information on all currently loaded kernel modules.
modload : loads kernel modules.
modunload : unloads kernel modules.
forceload : in the /etc/system file loads a module at boot time.

Passing a DB handler to an user defined function

It is pretty simply. Pass it like an ordinary variable.

Example here:

#!/opt/local/bin/perl

use db_connect;
use warnings;
use strict;


# More efficient than ./test_connection.pl because $0 makes only one DB connection

my $obj = db_connect->new();
my $db = $obj->connect_qora007_mir("qora007_mir");

print " \n";
&checkConnectionMIR_qora007($db);
&checkConnectionCIR_qora007($db);
print " \n";

$db->disconnect();



sub checkConnectionMIR_qora007($)
{
my $dbh = shift;

my $sql;
my $sth;
my $str;
my @row;

$sql = "select sysdate from dual";

$sth = $dbh->prepare($sql);
$sth->execute;

while((@row) = $sth->fetchrow_array())
{
$str = join(" " , map {defined $_ ? $_ : "(null)"} @row);
print "INSTANCE: $str\n";
}