实现mysql double变int取整方式

1. 整体流程

下面是实现mysql double变int取整方式的步骤表格：

步骤 操作内容
1 连接mysql数据库
2 创建一个新的数据库表
3 插入一些包含double类型数据的记录
4 使用CAST函数将double类型数据转换为int类型数据
5 查询转换后的int类型数据

2. 操作步骤及代码示例

步骤1：连接mysql数据库

// 连接mysql数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

步骤2：创建一个新的数据库表

// 创建一个新的数据库表
$sql = "CREATE TABLE my_table (
    id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    my_double DOUBLE
)";

if ($conn->query($sql) === TRUE) {
    echo "Table created successfully";
} else {
    echo "Error creating table: " . $conn->error;
}

步骤3：插入一些包含double类型数据的记录

// 插入一些包含double类型数据的记录
$sql = "INSERT INTO my_table (my_double) VALUES (3.14159), (2.71828), (1.41421)";

if ($conn->query($sql) === TRUE) {
    echo "Records inserted successfully";
} else {
    echo "Error inserting records: " . $conn->error;
}

步骤4：使用CAST函数将double类型数据转换为int类型数据

// 使用CAST函数将double类型数据转换为int类型数据
$sql = "SELECT CAST(my_double AS UNSIGNED) AS my_int FROM my_table";

$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "my_int: " . $row["my_int"] . "<br>";
    }
} else {
    echo "0 results";
}

步骤5：查询转换后的int类型数据

// 查询转换后的int类型数据
$sql = "SELECT * FROM my_table";

$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "id: " . $row["id"]. " - my_double: " . $row["my_double"]. " - my_int: " . $row["my_int"]. "<br>";
    }
} else {
    echo "0 results";
}

类图示例

classDiagram
    class Developer {
        - name: string
        - experience: int
        + teachBeginner(): void
    }
    class Beginner {
        - name: string
        - level: string
        + learn(): void
    }
    Developer <|-- Beginner

关系图示例

erDiagram
    Developer {
        string name
        int experience
    }
    Beginner {
        string name
        string level
    }

通过本文的指导，你可以实现mysql double变int取整方式。希望能够帮助到你，加油！