php中的mysql空查询 - 我得到了什么？ 资源ID？

I want to check whether my query is empty (has no rows). What is the best way of hecking it?

And what do I get in the following "$result" and "$row" (this is how I am aiming to solve this - if($result) or maybe using if($row) means that it is not empty. Any better suggestions?

Thanks.

       $result = mysql_query("SELECT * FROM table1 WHERE column1= '$var1'
                              AND column2 IN ('no','nein','nope')
                              AND timestamp BETWEEN '$date' AND NOW()"); 
       $row = mysql_fetch_assoc($result);    

Test this.

$result = mysql_query("SELECT * FROM table1 WHERE column1= '$var1'
                          AND column2 IN ('no','nein','nope')
                          AND timestamp BETWEEN '$date' AND NOW()"); 
$row = mysql_fetch_array($result);

if (mysql_num_rows($result) > 0) {
   echo $row['column name'];
}

You can use mysql_num_rows($result) get the number of rows, or you could see if $row === false;

$row will be the first row of the recordset OR false if the query has no results. $result will be a recordset resource if the query succeeded of false if it had an error.

If you are this early in the project and/or just learning please consider switching to the new DB interface PDO. At the least use Mysqli... the mysql extension youre using now is a bit outdated. It works, and sometimes its even required in legacy apps/sites, but it should be avoided if possible.

Use mysql_num_rows to get the row count.

$result will always be of type Resource if your query didn't fail.