Ti ringrazio per la pazienza ti posto la mia query, cosa devo cambiare?:
codice:
$conn1 = new mysqli($servername, $username, $password, $dbname);// Check connection
if ($conn1->connect_error) {
die("Connection failed: " . $conn1->connect_error);
}
$sql = "SELECT * FROM app_event WHERE category_id='21'";
$result = $conn1->query($sql);
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
$idecat = $row["id"];
$sql1="SELECT id FROM app_event_book WHERE start_date='2020-08-06' AND event_id IN('$idecat')";
$result1 = $conn1->query($sql1);
if ($result1=mysqli_query($conn1,$sql1))
{
// Return the number of rows in result set
$rowcount=mysqli_num_rows($result1);
echo $rowcount;
}
}
} else {
echo "";
}