How to Obtain Users ID and Put it in a Table - php

Question

I'm trying to make a football betting system based on the WordPress CMS. I apologize if this is a redundant question, but I've been searching through Google and a few Wiki's all day, and I haven't been able to find any clue to how this question is answered.
BACKGROUND INFORMATION:
I use:
MySQL
PHP
Navicat
Every time the user inputs two integers, corresponding to the goalscorings in a football match, on the php-scripted website, the two integers get sent off to the database table "bets", through an insert.php-file.
The insert.php looks like this:
<?php $con = mysql_connect("host","username","password"); if (!$con) { die('Could not connect: ' . mysql_error()); }
mysql_select_db("database", $con);
$sql="INSERT INTO bets (homebet, awaybet) VALUES ('$_POST[homebet]','$_POST[awaybet]')";
if (!mysql_query($sql,$con)) { die('Error: ' . mysql_error()); } echo "Thanks for betting!";
mysql_close($con); ?>
The php-form looks like this:
I have the following self-made tables: bets, teams, matches, and I have the WordPress table, wp-users, where each member is listed.
The bets table looks like this:
As you can see, the userid is empty - which it shouldn't be. It should contain the ID of the user, who entered the bet.
My two-part question is then..
How should I obtain the ID of the user and display it in the database table, bets? Perhaps WordPress have a code-snippet for it.
And finally, how should I attach a gameid to each match? Should I create a new form for each new match?
Thanks SO much in advance - I hope I was able to make this thread readable and easy to understand.
Frederick Andersen

Answer 1

You're missing quite some things here. I can't advise you how to manage the different games since I don't know what the rest of your application looks like.
Here are some pointers to get you going:
Don't create your own DB connection
Remove:
$con = mysql_connect("host","username","password"); if (!$con) { die('Could not connect: ' . mysql_error()); }
mysql_select_db("database", $con);
Add instead:
require_once($_SERVER['DOCUMENT_ROOT'].'/wp-load.php');
WordPress current user ID
Add this to top off script:
global $wpdb, $current_user;
get_currentuserinfo();
Change $sql code to this:
$sql= $wpdb->prepare("INSERT INTO `bets` (`userid`, `homebet`, `awaybet`) VALUES (%d, %d, %d)", $current_user->ID, $_POST['homebet'], $_POST['awaybet']);
I've also used the wpdb prepare function so your post data will be escaped before getting queried.
Also change this to use WP native querying.
Remove:
if (!mysql_query($sql,$con)) { die('Error: ' . mysql_error()); } echo "Thanks for betting!";
mysql_close($con);
Add instead:
$wpdb->query($sql)