错误的SQL结果条件

Question

I am having a bit of a problem with some code where a have a query which should come back false and it's returning true.

First I have an sql query to an id that does not exist:

$result = mysqli_query($con,"SELECT * FROM myTable WHERE id='1' "); //There no id with value of 1

Then I've added a var_dump to see what's on:

var_dump($result);

and after a condition:

if ($result==0) {
  echo 'No results where found';
} else {
  echo 'Some results where found';
}

Here's the result of the var_dump

object(mysqli_result)#2 (5) { ["current_field"]=> int(0) ["field_count"]=> int(12) ["lengths"]=> NULL ["num_rows"]=> int(0) ["type"]=> int(0) } 

Some results where found

The result should be: No results where found and as you can see above, it's return: Some results where found

What I'm I doing wrong here?

Answer 1

You need mysqli_num_rows() to see if the query has some rows something as

$count=mysqli_num_rows($result);
if($count == 0){
 // no result
}else{
 // there is data and do whatever you want
}

Check the documentation of mysqli_query() and the return part http://in2.php.net/mysqli_query

Returns FALSE on failure. For successful SELECT, SHOW, DESCRIBE or EXPLAIN queries mysqli_query() will return a mysqli_result object. For other successful queries mysqli_query() will return TRUE.

Answer 2

I think that your id field is an integer , so:

SELECT * FROM myTable WHERE id=1

should work