php mysql小数点后两位小数

CREATE TABLE `products` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `name` VARCHAR(255) NOT NULL,
  `price` DECIMAL(10, 2) NOT NULL
);

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检测连接
if ($conn->connect_error) {
  die("连接失败: " . $conn->connect_error);
}

$sql = "INSERT INTO products (name, price) VALUES ('Product A', 19.99)";
if ($conn->query($sql) === TRUE) {
  echo "新记录插入成功";
} else {
  echo "Error: " . $sql . "<br>" . $conn->error;
}

$conn->close();
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检测连接
if ($conn->connect_error) {
  die("连接失败: " . $conn->connect_error);
}

$sql = "SELECT id, name, price FROM products";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
  // 输出数据
  while($row = $result->fetch_assoc()) {
    echo "id: " . $row["id"]. " - Name: " . $row["name"]. " - Price: " . $row["price"]. "<br>";
  }
} else {
  echo "0 结果";
}
$conn->close();
?>

$price = number_format(19.99, 2); // 格式化为两位小数
$sql = "INSERT INTO products (name, price) VALUES ('Product A', $price)";

while($row = $result->fetch_assoc()) {
  $formatted_price = number_format($row["price"], 2);
  echo "id: " . $row["id"]. " - Name: " . $row["name"]. " - Price: " . $formatted_price . "<br>";
}