Hi im basically using cgi and DBI to create a few script. But early on I have found that im having problems with sql queries that use variables that are uninitialized at compile but become initialized at runtime. Below is a small sample of code:

#!/usr/bin/perl -w

use CGI;
use strict;
use DBI;

my $query = new CGI->new();



print $query->header("text/html"),


$query->start_html(-title => "Database Test"),

$query->h1("Database Test"),

my $user = $query->param("username"),

my  $db_handle = DBI->connect("dbi:mysql:database=test;host=localhost;
+user=root;")
  or die "Couldn't connect to database: $DBI::errstr\n";
   
my $sql = "SELECT * FROM users WHERE id = '$user'";

my $statement = $db_handle->prepare($sql)
        or die "Couldn't prepare query '$sql': $DBI::errstr\n";

$statement->execute()
        or die "Couldn't execute query '$sql': $DBI::errstr\n";
    
while (my $row_ref = $statement->fetchrow_hashref())
{
   
    
    print "<b>$row_ref->{email}</b>" ;
    
}

$db_handle->disconnect();

 print "<h1>Database Test</h1>";

    $query->end_html;
[download]

The output i get is

Database Test
(Username i enter in the form)DBI::db=HASH(0x838242c)
Database Test
[download]

if i change:

my $sql = "SELECT * FROM users WHERE id = '$user'";
[download]

to

my $sql = "SELECT * FROM users WHERE id = 1";
[download]

then I will get

Database Test
(Correct email address)
Database Test
[download]

the error i get when i run it is

Use of uninitialized value in concatenation (.) or string at login.pl 
+line 27.
[download]

line 27 being the sql statement. What can I do to use form data in my sql queries @_@ any help is much appreciated.

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