ok. I've updated it. I've designed it to be used once and then deleted. If you keep it and then accidentally run it again, it will possibly add all the records into your database again but more likely (and hopefully!) it will cock up and not adjust anything 
All you need to do is to edit 5 things, I've put them all at the top. First of all, the value for the variable $file. This should point to your text file. EG: 'http://mysite.com/files/businesses.txt'. Make sure you leave the single quotes in there!
Next, replace 'your MySQL host address', 'your name', 'your password' and 'database name' with the relevant information. I cannot find these out for you. Contact your administrator/support staff if you are unsure.
You may be able to use 'localhost' for the MySQL host address.
EDIT: Oh btw, I'm in the UK so I have no idea of the format of zip codes. I assume they are 5 digits, nothing else? If letters can go in zip codes or they can have more than 5 digits, then it will fail to save it correctly!
In addition, I was unsure of the phone number format. Because (+414)1111-111-111 (for example) is commonplace, it can take characters as well as numbers, up to a maximum of 20 characters.
If you need any of the script explaining or anything so you can understand it better, don't hesitate to ask 
PHP Code:
<?php
$file = 'location/of_file.txt';
$database = array(
'url' => 'your MySQL host address',
'name' => 'your name',
'pass' => 'your password',
'database' => 'database name');
mysql_connect($database['url'],$database['name'],$database['pass']) or die('Error connecting to MySQL: '.mysql_error());
echo 'Connected to MySQL<br>';
mysql_select_db($database['database']) or die('Error connecting to MySQL database: '.mysql_error());
echo 'Connected to Database<br>';
$query = "CREATE TABLE businesses(
id INT NOT NULL AUTO_INCREMENT,
PRIMARY KEY(id),
name VARCHAR(100) NOT NULL,
address VARCHAR(300) NOT NULL,
zip INT(5) NOT NULL,
phone VARCHAR(20) NOT NULL)";
mysql_query($query) or die('Error creating table: '.mysql_error());
echo 'Table Created<br>';
$array = file($file);
$business = array('name' => array(),'address' => array(), 'zip' => array(), 'phone' => array());
$line = 1;
$key = 0;
while (count($array) > 0)
{
switch ($line)
{
case 1:
$business[$key]['name'] = array_shift($array);
break;
case 2:
$business[$key]['address'] = array_shift($array);
break;
case 3:
$business[$key]['zip'] = array_shift($array);
break;
case 4:
$business[$key]['phone'] = array_shift($array);
break;
case 5:
break;
case 6:
$key++;
break;
}
if ($line >= 6)
$line = 1;
else
$line++;
}
foreach ($business as $newarray)
{
$query = "INSERT INTO businesses
(name,address,zip,phone) VALUES('{$newarray['name']}','{$newarray['address']}','{$newarray['zip']}','{$newarray['phone']}')";
mysql_query($query) or die('Error adding row: '.mysql_error());
echo 'Row data added<br>';
}
echo "Succesfully added all entries into the database. Be sure to delete both $file and this script to prevent duplicated entries in your database!";
?>
You will now have all the data stored in your database. You can use other scripts or utilities such as phpMyAdmin to access the data.