Warning: extract(): First argument should be an array in

[Geeza1973]

Below is the code I have:

<?php
include("db.php");
mysql_connect ($host, $user, $pass);
mysql_select_db ($database);
$result = mysql_query ("SELECT * FROM `highscore` ORDER BY score DESC LIMIT 10");
$row = @mysql_fetch_array ($result);
extract ($row);
echo "$player : $score ";
?>
 

The db.php file has my username, password, host, database name and table set to variables, which are correct.

I keep getting this error though:

Warning: extract(): First argument should be an array in folder/folder/folder/display_scores.php on line 7
 

Which is the extract ($row); line

Can anybody help me or point me in the right direction? It would be greatly appreciated. Thanks in advance.

[Atli]

Hi Geeza. Welcome to The Scripts!

The mysql_fetch_array() function is likely not able to read a row from the mysql_query() result resource. When that happens it returns FALSE, which triggers the warning you get when the extract() function tries to use it's result.

Try doing something more like this:

if($row = @mysql_fetch_array()) {
  extract($row);
  echo "$player - $score";
}
else {
  # MySQL query failed or returned no rows
}
 

Or if you want to show all the rows your query returned:

while($row = @mysql_fetch_array()) {
  extract($row);
  echo "<br />$player - $score";
}
 

[Geeza1973]

I tried both of your examples Atli. The good news is that both of you're examples got rid of the error. The bad news is that now I am getting nothing. I'm assuming there must be a problem in my db.php file . Its as if the database isn't even being accessed. I'm not 100% sure that what I set the $host variable to was correct. I'm waiting to hear back from my host company to find out the host name.

[Atli]

Try turning on php error messgaes.

[Geeza1973]

I added the lines to display any errors. Still nothing comes up. Because I was unsure of the host name in the db.php file I changed it to something else to see if that would cause errors. It did. When I changed it back to what it was originally the errors disappeared, so I'm guessing what I have as the host name is correct. I'm still waiting to hear back from my host company.

[pbmods]

Heya, Geeza.

Try

var_dump($row);

to make sure you're working with what you think you're working with.

If it's false, make sure that your sql query isn't generating an error:

echo mysql_error();
 

[Geeza1973]

Hi pbmods,
I first added the line: var_dump($row); to the bottom of my file and u/l it. In my browser I got the result NULL
I then added the line: echo mysql_error(); to the bottom of the file and u/l it. I just got the same result of NULL on the screen.

If it helps at all, my file now looks like this:

<?php
error_reporting(E_ALL);
ini_set('display_errors', True);
include("db.php");
mysql_connect ($host, $user, $pass);
mysql_select_db ($database);
while($row = @mysql_fetch_array()) {
   extract($row);
   echo "<br />$player - $score";
}
var_dump($row);
echo mysql_error();
?>

[pbmods]

Heya, Geeza.

Please use CODE tags when posting source code:

[CODE=php]
PHP code goes here.
[/CODE]

[pbmods]

Is this line in there somewhere, too?

$result = mysql_query ("SELECT * FROM `highscore` ORDER BY score DESC LIMIT 10");
 

[Geeza1973]

Ok I'll start using the [code] tags, sorry I didn't realise. I also didn't realise I'd deleted the line:

$result = mysql_query ("SELECT * FROM `highscore` ORDER BY score DESC LIMIT 10");
 

So I put that line back in and it now comes up saying:
NULL Table 'highscoreDB.highscore' doesn't exist
I checked to make sure all the spelling is correct and it is. I tried renaming highscoreDB to see what would happen. Half expecting it to say the same thing but instead it came back saying: NULL No Database Selected.

Now I am really confused why it says highscoreDB doesn't exist when I've set it up in phpMyAdmin. But yet when I rename highscoreDB to something completely different it doesn't say that that doesn't exist, it comes back saying 'No Database Selected'.

[pbmods]

Heya, Geeza.

You're getting a 'no database selected' error because on this line:

mysql_select_db ($database);
 

$database is still set to the previous name of the database. Because there is no database with the old name anymore, MySQL does not select a database.

[Geeza1973]

I changed the value of $database from "highscoreDB.highscore" to something else like "scoreDB.highscore". Not the name of the actual database itself. That is what is confusing me. Why is it when I change the value of $database to "scoreDB.highscore" does it not say "scoreDB.highscore doesn't exist", like it does with the correct name "highscoreDB.highscore" Instead it just says "database not selected."

[Geeza1973]

I found out what was causing the errors 'database not selected' and 'database not found'. In the table name of the database I had 'highscore' in one place and 'highScore' in another place. So I no longer get those errors but I still only have 'NULL' come up in my browser without any results from my database.

[pbmods]

Heya, Geeza.

Ooh, good call.

Despite Blizzard's incessant warnings to the otherwise (I will have a good laugh if this link gets removed), case-sensitive filesystems can be your friend.

And in this particular case, your worst enemy.

[Atli]

Heya, Geeza.

Ooh, good call.

Despite Blizzard's incessant warnings to the otherwise (I will have a good laugh if this link gets removed), case-sensitive filesystems can be your friend.

And in this particular case, your worst enemy.

Hehe, you got to love Blizzard :)
Weird that they wont just fix it. Looks like it's only the Installer that's having problems. Shouldn't be that hard either. Bit boring maybe :P

[Geeza1973]

Yeah I nearly kicked myself when I found it was something as simple as having an 's' when it should have been an 'S'. Maybe I'll stick to all lowercase from now on, at least while I'm still learning :) I'm still not getting any results from my database though.

[pbmods]

Heya, Geeza.

Is mysql_error() spitting anything out at you?

[Geeza1973]

No pbmods, its not giving me anything. The whole line I have is:

echo mysql_error();
 

And I have it right at the end of my code.

[pbmods]

Heya, Geeza.

Sounds like you might be good to go. What does this output?

$row = mysql_fetch_assoc($result);
print_r($row);
 

Note that I removed the '@' so as to make it easier to debug. I also changed mysql_fetch_array() to mysql_fetch_assoc() for greater efficiency.

[Geeza1973]

Hey pbmods,
Thanks man!
I added that code you gave me and I finally got a result. I got:

Array ( [player] => E-L-T [score] => 15000 )

As soon as I got that result I took another section of code you gave me:

while($row = @mysql_fetch_array()) {
   extract($row);
   echo "<br />$player - $score";
}
 

And edited it to:

while($row = mysql_fetch_assoc($result)) {
    print_r($row);
}
 

Which I'm quietly proud of :)
And got all the results from the database. The only difference between my results and the results in the tutorial I was following when this forum topic began. Is that my results have the 'Array' and [] => come up etc. Where as the results in the tutorial just had 'player_name : score'. Is that easy to fix?

[pbmods]

Heya, Geeza.

print_r() is a fantastic debugging function, but you are correct; its output is seldom useful for deployment.

The good news is that where you call print_r(), $row now contains all the data for one row in your MySQL result set.

This gives you two options:

• In the spirit of eventually creating a Data Abstraction Layer, you can copy your MySQL result set into an associative array:
  

  $resultSet = array();
  while( $_row = mysql_fetch_assoc($result) )
  {
      $resultSet[] = $_row;
  }
   

• Or you can just go ahead and process your data in the loop itself:
  

  while( $row = mysql_fetch_assoc($result) )
  {
      echo "
          <tr>
              <td>{$row['id']}</td>
              <td>{$row['score']}</td>
          </tr>";
  }
   

[Geeza1973]

Hey pbmods,
Thanks so much for all your help man!
I tried your first example and didn't get a result although I haven't read all of the info from the link you gave me.

The second example worked a treat, gave me the exact results I was looking for.

Thanks again for all your help dude, you're a lifesaver! Now I can carry on watching the tutorial I was working along with.
Thanks.

[pbmods]

Heya, Geeza.

Glad to hear you got it working! Good luck with your project, and if you ever need anything, post back anytime :)