PHP Mysql select - php

Question

I'm trying to select some rows from my database, and generate specific HTML where my selection finds something and other HTML when it does not.
This is my code. The problem is that it always finds no matches:
$pos = 0;
$con = mysqli_connect('localhost', 'user', 'pass', 'database');
if (mysqli_connect_error()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($con, "SELECT * FROM table1 where user = 'user'")
or die("Error: ".mysqli_error($con));
while ($row = mysqli_fetch_array($result)) {
$result2 = mysqli_query($con,"SELECT * FROM table2 where id = '"
.$row['id']."'") or die("Error: ".mysqli_error($con));
$dbpos = $row['pos'];
while ($row2 = mysqli_fetch_array($result2)) {
if ($dbpos == $pos) {
echo 'found<br/>';
} else {
echo 'empty<br/>';
}
$pos++;
}
}
mysqli_close($con);
I always get empty. What am I doing wrong?

Answer 1

Try making your query something like
Select * from table1
inner join table2
on table1.id=table2.id
Where table1.user='user'
This will do what you want in 1 query
If you get 1 result print found. If you get 0 then print empty

Answer 2

If you just want to determine if your query has an empty result or how many result was found, you can use mysqli_num_rows and remove your second while loop ($result2).
$noofrows=mysqli_num_rows($result2);
if($noofrows==0){
echo "Empty<br>";
}
else {
echo "There are ".$noofrows." record/s found.";
}

Answer 3

Try this. SQL joins can be very efficient depending on how your tables are structured.
//Query the DB for all of the rows in table2 where the table2 id column value
// is equal to the value of the id column value in table1
$query = "SELECT table2.*
FROM table1
INNER JOIN table2
ON table1.id = table2.id
WHERE table1.user = 'user'";
$result = mysqli_query($con, $query)or die(mysqli_error());
If you're expecting to return more than one row, the following might come in handy
$count = mysql_num_rows($result);
$i = 0;
while($row = mysqli_fetch_array($result)) {
$dbpos[$i] = $row['pos'];
$i++;
}
for($i=0;$i<$count;$i++) {
if($dbpos[$i] == $pos) {
echo 'found<br/>';
} else {
echo 'empty<br/>';
}
}
If not, then simply do this
while($row = mysqli_fetch_array($result)) {
$dbpos = $row['pos'];
}
if($dbpos == $pos) {
echo 'found<br/>';
} else {
echo 'empty<br/>';
}
More info about SQL joins here.