为什么这个代码行中的零

Question

I have found a reference in the tutorials that this 0 returns the first row but I "Don't Get It" What if there's more than 1 row such as in the function below?? (ie: I have a table of 200 users and this column "UsersName" is just one among 10 others so why the Zero?)

Could someone please spell out why this 0 is in this line of code??

Thanks

function member_count() {
    return mysql_result(mysql_query("SELECT COUNT(`UsersName`) FROM `users` WHERE `Active` = 1"), 0);
}

Answer 1

Couldn't you have looked up the PHP documentation? It's rather good...

string mysql_result ( resource $result , int $row [, mixed $field = 0 ] )

row

The row number from the result that's being retrieved. Row numbers start at 0.

http://php.net/manual/en/function.mysql-result.php

Imagine you done a SELECT * FROM users, where the table contains

name  | age
David | 29
John  | 18
Paul  | 26

Row 0 would be "David - 29", row 1 would be "John - 18", so forth.