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mysql_num_rows always returns 1

开发者 https://www.devze.com 2023-01-17 09:06 出处:网络
The result is always 1: $sql = \'SELECT COUNT(Vote) FROM \' . $table; $res = mysql_query($sql, $conn); $vote_total = mysql_num_rows($res);

The result is always 1:

$sql = 'SELECT COUNT(Vote) FROM ' . $table;
$res = mysql_query($sql, $conn);
$vote_total = mysql_num_rows($res);

I ran the $sql query in phpMyAdmin and it returns 3, so the query is not the problem. $vote_total is initialized globally to 0, so that 1 is coming from somewhere. What other information do I need to provide to make helping me easier?

Tha开发者_如何学Cnks, Ryan


mysql_num_rows returns the number of selected rows and not the fields of a certain row. Use mysql_fetch_row to fetch the row you have selected with your query:

$sql = 'SELECT COUNT(Vote) FROM ' . $table;
$res = mysql_query($sql, $conn);
$row = mysql_fetch_row($res);
$vote_total = $row[0];

You could also use mysql_result to fetch a row and get a certain field:

$vote_total = mysql_result($res, 0, 0);

This fetches the first row (zero based) and returns the first field (zero based).


There will only ever be one row. And in that row will be the count of votes.

$sql = 'SELECT COUNT(Vote) FROM ' . $table;
$res = mysql_query($sql, $conn);
$vote_array = mysql_fetch_array($res);
$vote_total = $vote_array[0];

If you want to count the number of votes with mysql_num_rows, you have to select ALL of the rows.


That query does return only one row. What you want is to retrieve the value from the query:

$row = mysql_fetch_array($res);
$vote_total = $row[0];


The tricky part is that even when the sql query contains a COUNT() statement, it is still a query result like any other. MySQL will return a row containg a single column with the number of rows that would have been returned, should you have issued a reglar query. mysql_num_rows() on the other hand, just counts the number of rows in the result of the query that was actually executed. In this case it is always a single row.

What you want is:

$sql = 'SELECT COUNT(Vote) FROM ' . $table;
$res = mysql_query($sql, $conn);
$data = mysql_fetch_row($res);
$vote_total = $data[0];
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