Updating a Row in PostgreSQL with PHP - php

Question

I was wondering what the syntax was in PHP to update a row in a PostgreSQL database. I have made a login page that checks a UserName and Password from a database, then it goes to a page where it displays all the user info from the database for that user name. I am trying to allow the user to change some of the columns, like password, name, etc. So I added another page that has fields for each of the columns I want to change.
This is the code I have for the query:
if(array_key_exists('save',$_POST))
{
$firstname=$_POST['ifirstname'];
$lastname=$_POST['ilastname'];
$email=$_POST['iemail'];
$password=$_POST['ipassword'];
$conn_string='host=#### port=#### dbname=###### user=####### password=######';
$dbconn=pg_connect($conn_string) or die('Connection failed');
$query="UPDATE project.customer SET FirstName='$firstname',
LastName='$lastname',Email='$email',Password='$password')
WHERE UserName=$1";
$result=pg_query($dbconn,$query);
$row_count= pg_num_rows($result);
pg_free_result($result);
pg_close($dbconn);
}
This is for the fields:
<div id="header">UPDATE USER INFO</div>
<form id="testform" name="testform" method="post" action="" >
<p> <label for="ifirstname">First Name:</label>
<input name="ifirstname" type="text" id="ifirstname"/>
</p>
<p> <label for="ilastname">Last Name:</label>
<input name="ilastname" type="text" id="ilastname"/>
</p>
<p> <label for="iemail">E-Mail:</label>
<input name="iemail" type="text" id="iemail"/>
</p>
<p>
<label for="ipassword">Password:</label>
<input name="ipassword" type="password" id="ipassword"/>
</p>
<p>
<label for="iconfpass">Confirm Password:</label>
<input name="iconfpass" type="password" id="iconfpass"/>
</p>
<p>
<input type="submit" name="save" value="Register"/>
</p>
</form>

Answer 1

I think it must be like this. Also make user to write old password when changing data for security reason. Also dont forget to filter your data before using in query to avoid sql injection attacks
$query="UPDATE project.customer
SET (FirstName,LastName,Email,Password) =
('$firstname','$lastname','$email','$password')
WHERE UserName= '$1' and Password = '$oldpassword'";

Answer 2

Why not just use standard SQL syntax?
Update project.customer Set
"FirstName" = '$firstname',
...
Where ...
The main difference in Postgres is that you usually quote the column names.