The mysql_query function executes a query againts a DBM and just that, it
delivers the query to the DBM, if the DBM can execute the query, it returns
a positive integer, if the DBM can not execute the query, it returns 0 or
false, can't remember exactly right now.

So, it will return a positive integer no matter the query found any records
at all, so you must use mysql_num_rows() in order to find out how many
records the query returned.

-----Original Message-----
From: Tim McGeary [mailto:[EMAIL PROTECTED]
Sent: Viernes, 27 de Abril de 2007 10:56 a.m.
Subject: [PHP-DB] handling a SELECT that returns nothing

I am writing a web php application that is processing a request form.
There are multiple times when I need to check if a record exists (i.e.
user record) and if so, check the inputted data against the data already
in the database and confirm whether the inputted data should update the

I am getting stuck in my check of whether a record yet exists.  I
thought that $result in the code snippet below would be empty, so I
thought I could use the empty() function in an if conditional.  But a
later conditional on the returned result of 0 never happened, so I
echoed the $result of the mysql_query.

I have a completely empty database and my initial test should load my
new record, but I am finding that the $result is being filled with

Resource id #4

from the mysql_query.  Why?  What does that mean?  Why wouldn't it be
empty?  And more importantly, how do I this check properly?


function record_exist($select_value, $search_value, $table, $field) {

    $query = "SELECT $select_value FROM $table WHERE $field =

    $result = mysql_query("SELECT $select_value FROM $table WHERE
$field='{$search_value}'") or die(mysql_error());

    echo "$result"."<br>";

    if (empty($result)) {
       return 0;
    else {
       return $result;

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