too long

I want to prepare an SQL insert statement inside PHP for loop, my statement is something like this

$insert_stmt = "";
for($x=1; $x<=$all_property[duration]; $x++) {
    $insert_stmt .= "INSERT INTO `schedule` VALUES ($all_property[serial], $_POST[Day$x])";

echo $insert_stmt;
mysqli_free_result($insert_stmt);   // Free result set for next query
}

wherein I expect the result to be like

INSERT INTO `schedule` VALUES ($all_property[serial], $_POST[Day1] //for first loop
INSERT INTO `schedule` VALUES ($all_property[serial], $_POST[Day2] //for second loop

And so on, but I am getting error

syntax error, unexpected '$x' (T_VARIABLE), expecting ']' in schedule.php on line 163

so, if any one can help me rectify what is wrong in my query.

Updated:

As the fields are not constant and also they are string, you need to quote them, so just use this line:

$insert_stmt = "INSERT INTO schedule VALUES (‘".$all_property[serial]."’, ‘".$_POST["Day".$x]."’)";

no, day1 and day2 are not constant values, these are the fields $_POST[] fileds generated from below table

for ($x = 1; $x <= $all_property['duration']; $x++) { $date_result = mysqli_query($connection, "SELECT DATE_ADD(dur_from,INTERVAL $x-1 DAY) AS dur_from FROM batch_details WHERE serial=1"); $today_date = mysqli_fetch_assoc($date_result); echo' " size="12" value=""> " size="20" placeholder="Subject or Topic" maxlength="50" required> " size="18" placeholder="Room No" maxlength="3" pattern="[0-9]{3}" required> " size="18" placeholder="Main Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> " size="18" placeholder="Subs Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> " size="20" placeholder="Subject or Topic" maxlength="50" required> " size="18" placeholder="Room No" maxlength="3" pattern="[0-9]{3}" required> " size="18" placeholder="Main Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> " size="18" placeholder="Subs Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> " size="20" placeholder="Subject or Topic" maxlength="50" required> " size="18" placeholder="Room No" maxlength="3" pattern="[0-9]{3}" required> " size="18" placeholder="Main Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> " size="18" placeholder="Subs Lecturer ID" maxlength="3" pattern="[A-Za-z]{3}" required> ';

wherein, depending on the "duration" (which is basically no of days) the input field gets generated with name="Day$x" and then again I have to insert this value to another table.

Yes, the above line did solve the problem. And so the issue may be closed now.