How to link and display MySQL data from two different tables?

Question

I have two tables named "stats" and "users"

users table has all the typical user data like id,username,password,email(columns)
stats table has id,attack, defense,ostats,gold,food(columns)

I want to display data from these two tables side by side and have the data linked through their IDS For example,

 Rank   user_uid   ostats     attack    defense    gold 
   1    Test        10          5         5        100
   2    Test2       8           2         6        60
   3    Test3       6           5         1        40

Username is from table "users" and the rest of them are from table "stats"

So first I want to know how to link and display the data from the same ID, like Username(user_id=1) and ostats,attack,defense,gold,food(id=1)

Then I want them in order by their "ostats" (I don't have a column named "rank" in any table yet, just don't know how to create the rank using overall stats)

Answer 1

You could do something like (untested)

SELECT u.username, s.overall, s.attack, s.defense, s.gold 
FROM stats s JOIN users u on s.user_uid = u.id 
ORDER BY s.overall;

Possible solution to ranking:

set @row_number=0;
SELECT (@row_number:=@row_number+1) as rank, u.username, s.overall, s.attack, s.defense, s.gold 
FROM stats s JOIN users u on s.user_uid = u.id 
ORDER BY s.overall;

Another, horrible looking attempt:

set @row_number = (select count(*) from users) + 1;
select (@row_number:=@row_number-1) as rank,  u.username, s.overall from 
stats s join users u on s.user_uid = u.id order by s.overall desc;
set @row_number = 0;

Here in PHP code, you have to run it as two queries to set the variable, then run the actual ranking query. This way, the rank variable is always set to 0 when running this. Note that I've used different table and column names, just to simplify things a little. Remember to adjust to your specific needs.

// connect to database
$conn = mysqli_connect("localhost", "user", "password", "database");
// this query will set a variable to 0.
$setSql = "SET @row_number = 0;";
// run the query. This will return a boolean - true or false, depending on whether or not the query ran successfully
$variableSet = mysqli_query($conn, $setSql);
// if the query ran successfully
if($variableSet){
    // setup the actual ranking query
    $statsSql = "select 
                     (@row_number:=@row_number+1) as rank,
                     u.id,
                     u.username,
                     s.overall
                 from
                     mstats s 
                 join 
                     musers u
                 on 
                     s.muser = u.id
                 order by 
                     s.overall desc;";
    $ranks = mysqli_query($conn, $statsSql);
    if(!$ranks){
        // dump error from rank query
        var_dump($conn->error); 
    } else {
        // dump results as associative array
        var_dump($ranks->fetch_all(MYSQLI_ASSOC));
    }
} else {
    // dump errors from setting variable
    var_dump($conn->error); 
}

For me, the results dump looks like this:

array (size=3)
  0 => 
    array (size=4)
      'rank' => string '1' (length=1)
      'id' => string '2' (length=1)
      'username' => string 'Bar' (length=3)
      'overall' => string '1000' (length=4)
  1 => 
    array (size=4)
      'rank' => string '2' (length=1)
      'id' => string '6' (length=1)
      'username' => string 'Tom' (length=3)
      'overall' => string '7' (length=1)
  2 => 
    array (size=4)
      'rank' => string '3' (length=1)
      'id' => string '1' (length=1)
      'username' => string 'Foo' (length=3)
      'overall' => string '3' (length=1)