Can someone take these 3 files and make one big database connection string in php file from them?

And remove the old connections from them and make like a include or require for those 3.

This is what I mean:

PHP Code:

<?
// Connect to the database
mysql_connect ('localhost', 'database Username', 'database password') ;
mysql_select_db ('database name');
?>

These are the 3 files
File 1:

PHP Code:

<?php
/* fill in your database name */
$database_name = "db_name";
/* connect to MySQL */
if (!$link = mysql_connect("localhost", "username", "password")) {
  die("Could not connect: " . mysql_error());
}
/* specify table name */
  $sql = "DELETE FROM $database_name.Persons";
  if($result = mysql_query($sql)){
    echo "";
  }
  else{
    echo "Error deleting from Persons. MySQL Error: " . mysql_error() . "";
  }

?>

File 2:

PHP Code:

<?php
$con = mysql_connect("localhost","username","password");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }
mysql_select_db("db_name", $con);
$result = mysql_query("SELECT * FROM Persons");
while($row = mysql_fetch_array($result))
  {
  echo "";
  echo "First Name: " . $row['FirstName'] . "";
  echo "<br>";
  echo "Last Name: " . $row['LastName'] . "";
  echo "<br>";
  echo "******************************";
  echo "<br>";
  }
echo "</table>";
mysql_close($con);
?>

File 3:

PHP Code:

<?php
$con = mysql_connect("localhost","username","password");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("db_name", $con);

$sql="INSERT INTO Persons (FirstName, LastName)
VALUES
('$_POST[Username]','$_POST[Password]')";

if (!mysql_query($sql,$con))
  {
  die('Error: ' . mysql_error());
  }
echo "";

mysql_close($con)
?>

What is it that you are trying to do with these scripts? The first example you posted is literally how to connect to a database server and select the database you want. What are the extra functions you are incorporating in the other three files?

If you mean a file so you dont have to type up database connection everytime.

1) Create a file e.g. config.php
2) Add

PHP Code:

$con = mysql_connect("localhost","username","password") 


to the file and fill it out so the connection works.
3) open up the three files and replace

PHP Code:

$con = mysql_connect("localhost","username","password"); 


with

PHP Code:

@include('./config.php'); 


Thats the answer to the title anyway.