使用foreach循环填充数组？

I'm trying to populate the array for the variable $example_data. I have an array of Mass' and dates that I want to populate this array with. However I do not know how to create a new array entry for each $mass[$x] and $date[$x] that I want to store. I've tried putting a foreach loop inside the $example_data = array( but it didnt work.

This is what I want it to do, but doesn't work:

$example_data = array(
    foreach($exer->results() as $ex){
        $mass = $ex->Mass;
        $date = $ex->Date;

        array($date,$mass),
);

This is what I've tried but not sure how to complete it:

$userID = $user->data()->id;

$sql = "SELECT * FROM userdetails WHERE UserID = ".$userID."";
$details = DB::getinstance()->query($sql);

$x = 1;

foreach($details->results() as $detail){
    /** getting data from each record from field Mass and storing it in $mass array **/
    $mass[$x] = $detail->Mass;
    $date[$x] = $detail->Date;

    $x++;
}

$x = 1;

$example_data = array(
        array($date[$x],$mass[$x]),
        /** I want it to create a new array entry for each $mass[] **/
);

It depends on the type of database you're using...

For example if you're using MySQL, it's mysqli_fetch_assoc()

You're trying to fetch a result set into an associative array but the result set itself is an associative array

try...

$sql = "SELECT * FROM userdetails WHERE UserID = ".$userID."";
$details = DB::getinstance()->query($sql);

$example_data = array(
  array("Mass"),
  array("Date")
);


while($row = $details->fetch_assoc()) {
    array_push($example_data['Mass'], $row['name_of_mass_column_in_db']);
    array_push($example_data['Date'], $row['name_of_date_column_in_db']);
  }
}

Basically, you can just fetch an associative array instead of populating an associative array with an associative array...