Confirming A Database Row was deleted via PHP in aJax/jQuery - php

Question

I'm trying to figure out the best way to relay back to ajax if the POST data sent to the .php file successfully deleted the data from the database. I'm not sure what to phrase what I'm looking for, but essentially I thought about a 'if() { } else { }' statement perhaps, but I'm not sure how to send the data back correctly into the success:function. Here is the basic code below that ajax is using. The PHP file is just standard code for running a deletion via php/mysqli.
$.ajax({
url: "../ajax/modules/delete-from-db.php",
data:{},
type:'POST',
success:function(data){
//IF() {
//EXECUTE SUCCESS & REMOVE DIV
//} ELSE {
//GIVE NOTICE OF DELETION FAILURE
//}
}
});
So anyone have any ideas how I could accomplish this?

Answer 1

On your php. depends on what you are using, you can check if the query was successful or not. then you can add anything on your return statement that you could use on your ajax success funtion.
Example:
on the php side using PDO
$success = true;
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
$sql = "DELETE FROM MyGuests WHERE id=3";
$conn->exec($sql);
} catch (PDOException $e) {
$success = false;
}
return json_encode([
'success' => $success
])
Then on ajax. you can use this
$.ajax({
url: "../ajax/modules/delete-from-db.php",
data:{},
type:'POST',
success:function(data){
IF(data.success) {
//EXECUTE SUCCESS & REMOVE DIV
} ELSE {
//GIVE NOTICE OF DELETION FAILURE
}
}});

Answer 2

Some changes in your php file. if delete query return success then return true or 1 otherwise false or 0.
$.ajax({
url: "../ajax/modules/delete-from-db.php",
data:{},
type:'POST',
success:function(data){
if(data == 1){
alert("success");
} else {
alert("error");
}
}
});

Answer 3

it depends on what you send back from your php script, i recommend JSON which you could format as such
{
status:"success",//or error if failed
message:"record was successfully deleted"
}
in the php script you could have a Boolean flag to check if the record was deleted eg:
if($deleteFlag){
$response = array('status'=>'success', 'message'=>'record was successfully deleted');
} else {
$response = array('status'=>'error', 'message'=>'could not delete record!');
}
header('Content-type: application/json');
echo json_encode($response);