foreach $row[key] rename $key

[geiger]

It it possible to write some sort of loop to simplify lists such as the following?

$mid=            $row['mid'];
$mbid=            $row['mbid'];
$make=            $row['make'];
$model=            $row['model']; 

[CWebguy]

I'm not sure what you are trying to say.

[geiger]

After a mySQL query, for instance, all my data is read into $row via mysql_fetch_array(). When I use the values later in the script, I'd like to be able to refer to simply the field name rather than $row['field'], so I've written out long lists transferring the values to corresponding variables.

Is there some sort of foreach loop I can run to do this for the entire array without having to write out each variable individually?

[SJH]

foreach($row as $key => $value) {
  $$key = $value;
} 

You should be careful with this, though, in case you overwrite another variable needed by your script. You might be better off prefixing the field names, like this:

foreach($row as $key => $value) {
  $r_{$key} = $value;
} 

This would prefix all the variables with r_

[AnthonySterling]

Sure, take a look at extract().

Use it carefully though.

[geiger]

Thanks for the function. Could you please explain why using extract() on input variables is bad?

[AnthonySterling]

As SJH stated, in longer scripts, it would be far too easy for extract to overwrite an existing, trusted variable into an unchecked, unsanitised user defined variable.

Havoc man, HAVOK!

[geiger]

Oh, didn't see SJH's post. Sorry about that.
Your foreach does the same thing as extract(), right?

Thanks

[crmalibu]

extract has options for how it should behave should a collision or invalid variable name be encountered.

[SJH]

Your foreach does the same thing as extract(), right?

Pretty much yes, but I'd recommend the use of extract() instead of my original suggestion.

I always try and make a point of remembering that this function exists but it always slips my mind when I need to use it, and consequently end up using a foreach loop. Maybe I should get it tattooed on my forearm.

[geiger]

It's useful Just to make sure, is there anything wrong with how I'm doing this?

$row = mysql_fetch_array( $sql);
        extract( $row, EXTR_OVERWRITE );
        
        $notes = htmlentities( $notes );
        $fueltype = htmlentities( $fueltype );
        $strategy= htmlentities( $strategy );

echo "$cid, $notes"; 

[crmalibu]

overwrite would be correct. It's a good idea to explicitly list your columns in your sql query(for more reasons than this). If you're using the star, eg SELECT *, then if you every change the table column names, or add new ones, now all of a sudden you have new variables floating around your script because of extract.

[geiger]

Yes, I never use *. Here's a sample of how I'm fetching data right now. I need to add parameterizing still, and also validate the data going in. Then—if I'm right—I'll be secure?

$sql = mysql_query(
    " SELECT
        calc_gallons,
        calc_mpg,
        cid,
        cpg,
        enddate,
        fueltype,
        in_gallons,
        in_miles,
        in_mpg,
        notes,
        strategy,
        tid
    FROM
        fe_tanks
    WHERE
        tid = $tid ")
    or
        die( mysql_error() );

$row = mysql_fetch_array( $sql );
extract( $row, EXTR_OVERWRITE );

$notes = htmlentities( $notes );
$fueltype = htmlentities( $fueltype );
$strategy = htmlentities( $strategy );