Discussion: Select Single Column Using MySQL

[charles07]

have you ever wondered how to select a single coloumn from mysql using php, then checking whether a value or variable exist in the resulting array... well here is the code

$busid = '5412';
$results    =   mysql_query("SELECT `myname` FROM mytable WHERE myuser = 'user'");
        while($rows = mysql_fetch_array($results))
        {   
            $colnames[] = $rows['myname'];
        }
        if(!in_array($busid, $colnames))die("Access denied");

[Dormilich]

why going to the extend of using arrays? just get the count: SELECT COUNT() FROM mytable WHERE myuser = ? AND `myname` = ?

[NeoPa]

This wasn't close to Article quality, but may prove useful as the seed for a discussion.

[charles07]

thanks Dormilich,

i think you are right. let me try out your code & would get back to you.

[charles07]

thanks Dormilich

i used the below query, now it works fine,

SELECT `myname` FROM mytable WHERE myuser = 'user' and myname='5412'

Is there any difference between the above query & your query(SELECT COUNT() FROM mytable WHERE myuser = ? AND `myname` = ?), which is better?

iam a enthusiastic newbie to PHP, googled the same topic but couldn't get an answer, now it looks fine

[Dormilich]

Is there any difference between the above query & your query

there is. my query will always return one result (the number of rows) while your query returns all matching rows, which a) can be no results at all and b) returns redundant information (the myname field)

[charles07]

but how do i check whether the result is above 0

[Dormilich]

it is the result* of my query. you can directly use it in a comparison.

e.g. by using PDOStatement->fetchColumn( )