mysqli pull decimal value from db - php

Question

I'm trying to pull a decimal from my database, but when I try it's trying to make it an int and I don't know how to fix it because I'm stupid and I don't even deserve to be called a programmer. Can someone please help?
if (isset($_POST['Add'])) {
$Date = $_POST['Date'];
$Amount = $_POST['Amount'];
$LegalFees = 0.00;
$CheckID = $_POST['Check_ID'];
$DateAdded = date("Y/m/d", strtotime($_POST['Date']));
$result = mysqli_query($conn, "SELECT CheckID FROM checks WHERE CheckID='" . $CheckID . "'");
$CurrentPayment = mysqli_query($conn, "SELECT payments FROM checks WHERE CheckID='" . $CheckID . "'");
$TotalPayment = $Amount + $CurrentPayment;
if (mysqli_num_rows($result) > 0) {
$sqlinsert = $conn->query("INSERT INTO payments (Date,Amount,LegalFees,CheckID)Values('{$DateAdded}','{$Amount}','{$LegalFees}','{$CheckID}')");
$sqlupdate = $conn->query("UPDATE checks SET payments=" . $TotalPayment . " WHERE checkID=" . $CheckID . "");
} else {
$_SESSION["CheckIDFail"] = "Yes";
}
}
So basically it's supposed to select the payment in the db which is a decimal and store it into $CurrentPayment, but it can't because it's trying to make the decimal an int.
The rest of the code I don't really have a problem with, it works as it should. Just need to know how to make it pull a decimal correctly. I think it has to do with fetch or something? I don't know, someone please help this pathetic person?

Answer 1

I think the problem is trying to convert a result set (an array) to a number. PHP doesn't care whether your number is a decimal or an integer.
$Date = $_POST['Date'];
$Amount = $_POST['Amount'];
$LegalFees = 0.00;
$CheckID = $_POST['Check_ID'];
$DateAdded = date("Y/m/d", strtotime($_POST['Date']));
$result = mysqli_query($conn,
"SELECT payments FROM checks WHERE CheckID='" . $CheckID . "'")
or die(mysqli_error($conn));
$currentPayment = 0;
if (mysqli_num_rows($result) > 0){
// Get the "row" from the "result set".
// While loop is only added to illustrate the method of iterating through the results
// If you only expect one row in the output, this should still work fine
while($row = mysqli_fetch_assoc($result)){
$currentPayment += $row['payments'];
}
$TotalPayment = $Amount + $currentPayment;
mysqli_query($conn, "INSERT INTO payments (Date,Amount,LegalFees,CheckID)
values('{$DateAdded}','{$Amount}','{$LegalFees}','{$CheckID}')")
or die(mysqli_error($conn));
mysqli_query($conn, "UPDATE checks SET
payments=" . $TotalPayment . " WHERE checkID=" . $CheckID . "")
or die(mysqli_error($conn));
}
else {
// No rows returned
$_SESSION["CheckIDFail"] = "Yes";
}
A couple of things:
Maintain consistency in the type of queries within a program (in fact, even within an application) as a whole. Try not to switch back and forth between procedural (mysqli_query()) and object oriented ($conn->query) approach.
Use Prepared Queries to prevent the threat of SQL injections in your query - How to create a secure mysql prepared statement in php?
It's all right to stumble once in a while :)