如何获取php mysql查询中的行数？

Question

im trying to use this query:

mysql_query("SELECT COUNT(*) FROM Users WHERE (Username=" + $username + "AND Hash=" + $hash + ")")

to return the number of rows for authentication in a php script. but this doesnt return an int? how do I use the return value to get the number of rows?

Answer 1

You can use mysql_fetch_array to fetch rows from the result:

$result = mysql_query("SELECT COUNT(*) FROM Users WHERE ...") or die(mysql_error());
$row = mysql_fetch_array($result);
echo $row[0];

Or since you only need to fetch a single value you can do this more briefly using mysql_result :

$result = mysql_query("SELECT COUNT(*) FROM Users WHERE ...") or die(mysql_error());
echo mysql_result($result, 0);

I'd also suggest that you look at parameterized queries instead of building your SQL queries using string concatenations.