mysqladmin --version

mysqladmin  Ver 8.0.37 for Win64 on x86_64 (MySQL Community Server - GPL)

net start mysql

net stop mysql

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

[mysql.server]
user=mysql
basedir=/var/lib

[safe_mysqld]
err-log=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

use RUNOOB

CREATE DATABASE 数据库名;

CREATE DATABASE mydatabase
  CHARACTER SET utf8mb4
  COLLATE utf8mb4_general_ci;

CREATE DATABASE IF NOT EXISTS mydatabase;

mysqladmin -u your_username -p create your_database

CREATE DATABASE your_database;

mysqladmin -u your_username -p create your_database \
  --default-character-set=utf8mb4 \
  --default-collation=utf8mb4_general_ci

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('连接错误: ' . mysqli_error($conn));
}
echo '连接成功<br />';
$sql = 'CREATE DATABASE RUNOOB';
$retval = mysqli_query($conn,$sql );
if(! $retval )
{
    die('创建数据库失败: ' . mysqli_error($conn));
}
echo "数据库 RUNOOB 创建成功\n";
mysqli_close($conn);
?>

DROP DATABASE <database_name>;        -- 直接删除数据库，不检查是否存在
或
DROP DATABASE [IF EXISTS] <database_name>;

mysqladmin -u your_username -p drop your_database

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
echo '连接成功<br />';
$sql = 'DROP DATABASE RUNOOB';
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
    die('删除数据库失败: ' . mysqli_error($conn));
}
echo "数据库 RUNOOB 删除成功\n";
mysqli_close($conn);
?>

USE database_name;

mysql -u your_username -p -D your_database

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
echo '连接成功';
mysqli_select_db($conn, 'RUNOOB' );
mysqli_close($conn);
?>

CREATE TABLE table_name (
    column1 datatype,
    column2 datatype,
    ...
);

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL,
    email VARCHAR(100) NOT NULL,
    birthdate DATE,
    is_active BOOLEAN DEFAULT TRUE
);

CREATE TABLE mytable (
    id INT PRIMARY KEY,
    name VARCHAR(50)
) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

CREATE TABLE IF NOT EXISTS `runoob_tbl`(
   `runoob_id` INT UNSIGNED AUTO_INCREMENT,
   `runoob_title` VARCHAR(100) NOT NULL,
   `runoob_author` VARCHAR(40) NOT NULL,
   `submission_date` DATE,
   PRIMARY KEY ( `runoob_id` )
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

DROP TABLE table_name ;    -- 直接删除表，不检查是否存在
或
DROP TABLE [IF EXISTS] table_name;

mysqladmin -u your_username -p drop your_table

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('连接失败: ' . mysqli_error($conn));
}
echo '连接成功<br />';
$sql = "DROP TABLE runoob_tbl";
mysqli_select_db( $conn, 'RUNOOB' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
  die('数据表删除失败: ' . mysqli_error($conn));
}
echo "数据表删除成功\n";
mysqli_close($conn);
?>

INSERT INTO table_name (column1, column2, column3, ...)
VALUES (value1, value2, value3, ...);

INSERT INTO users
VALUES (NULL,'test', 'test@runoob.com', '1990-01-01', true);

INSERT INTO users (username, email, birthdate, is_active)
VALUES
    ('test1', 'test1@runoob.com', '1985-07-10', true),
    ('test2', 'test2@runoob.com', '1988-11-25', false),
    ('test3', 'test3@runoob.com', '1993-05-03', true);

root@host# mysql -u root -p password;
Enter password:*******
mysql> USE RUNOOB;
DATABASE changed
mysql> INSERT INTO runoob_tbl 
    -> (runoob_title, runoob_author, submission_date)
    -> VALUES
    -> ("学习 PHP", "菜鸟教程", NOW());
Query OK, 1 ROWS affected, 1 warnings (0.01 sec)
mysql> INSERT INTO runoob_tbl
    -> (runoob_title, runoob_author, submission_date)
    -> VALUES
    -> ("学习 MySQL", "菜鸟教程", NOW());
Query OK, 1 ROWS affected, 1 warnings (0.01 sec)
mysql> INSERT INTO runoob_tbl
    -> (runoob_title, runoob_author, submission_date)
    -> VALUES
    -> ("JAVA 教程", "RUNOOB.COM", '2016-05-06');
Query OK, 1 ROWS affected (0.00 sec)
mysql>

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('连接失败: ' . mysqli_error($conn));
}
echo '连接成功<br />';
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
 
$runoob_title = '学习 Python';
$runoob_author = 'RUNOOB.COM';
$submission_date = '2016-03-06';
 
$sql = "INSERT INTO runoob_tbl ".
        "(runoob_title,runoob_author, submission_date) ".
        "VALUES ".
        "('$runoob_title','$runoob_author','$submission_date')";
 
 
 
mysqli_select_db( $conn, 'RUNOOB' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
  die('无法插入数据: ' . mysqli_error($conn));
}
echo "数据插入成功\n";
mysqli_close($conn);
?>

SELECT column1, column2, ...
FROM table_name
[WHERE condition]
[ORDER BY column_name [ASC | DESC]]
[LIMIT number];

-- 选择所有列的所有行
SELECT * FROM users;

-- 选择特定列的所有行
SELECT username, email FROM users;

-- 添加 WHERE 子句，选择满足条件的行
SELECT * FROM users WHERE is_active = TRUE;

-- 添加 ORDER BY 子句，按照某列的升序排序
SELECT * FROM users ORDER BY birthdate;

-- 添加 ORDER BY 子句，按照某列的降序排序
SELECT * FROM users ORDER BY birthdate DESC;

-- 添加 LIMIT 子句，限制返回的行数
SELECT * FROM users LIMIT 10;

-- 使用 AND 运算符和通配符
SELECT * FROM users WHERE username LIKE 'j%' AND is_active = TRUE;

-- 使用 OR 运算符
SELECT * FROM users WHERE is_active = TRUE OR birthdate < '1990-01-01';

-- 使用 IN 子句
SELECT * FROM users WHERE birthdate IN ('1990-01-01', '1992-03-15', '1993-05-03');

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
 
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl';
 
mysqli_select_db( $conn, 'RUNOOB' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . mysqli_error($conn));
}
echo '<h2>菜鸟教程 mysqli_fetch_array 测试</h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = mysqli_fetch_array($retval, MYSQLI_ASSOC))
{
    echo "<tr><td> {$row['runoob_id']}</td> ".
         "<td>{$row['runoob_title']} </td> ".
         "<td>{$row['runoob_author']} </td> ".
         "<td>{$row['submission_date']} </td> ".
         "</tr>";
}
echo '</table>';
mysqli_close($conn);
?>

SELECT column1, column2, ...
FROM table_name
WHERE condition;

SELECT * FROM users WHERE username = 'test';

SELECT * FROM users WHERE username != 'runoob';

SELECT * FROM products WHERE price > 50.00;

SELECT * FROM orders WHERE order_date < '2023-01-01';

SELECT * FROM employees WHERE salary >= 50000;

SELECT * FROM students WHERE age <= 21;

SELECT * FROM products WHERE category = 'Electronics' AND price > 100.00;

SELECT * FROM orders WHERE order_date >= '2023-01-01' OR total_amount > 1000.00;

SELECT * FROM customers WHERE first_name LIKE 'J%';

SELECT * FROM countries WHERE country_code IN ('US', 'CA', 'MX');

SELECT * FROM products WHERE NOT category = 'Clothing';

SELECT * FROM orders WHERE order_date BETWEEN '2023-01-01' AND '2023-12-31';

SELECT * FROM employees WHERE department IS NULL;

SELECT * FROM customers WHERE email IS NOT NULL;

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
 
// 读取 runoob_author 为 RUNOOB.COM 的数据
$sql = 'SELECT runoob_id, runoob_title, 
        runoob_author, submission_date
        FROM runoob_tbl
        WHERE runoob_author="RUNOOB.COM"';
 
mysqli_select_db( $conn, 'RUNOOB' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . mysqli_error($conn));
}
echo '<h2>菜鸟教程 MySQL WHERE 子句测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = mysqli_fetch_array($retval, MYSQLI_ASSOC))
{
    echo "<tr><td> {$row['runoob_id']}</td> ".
         "<td>{$row['runoob_title']} </td> ".
         "<td>{$row['runoob_author']} </td> ".
         "<td>{$row['submission_date']} </td> ".
         "</tr>";
}
echo '</table>';
// 释放内存
mysqli_free_result($retval);
mysqli_close($conn);
?>

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;

UPDATE employees
SET salary = 60000
WHERE employee_id = 101;

UPDATE orders
SET status = 'Shipped', ship_date = '2023-03-01'
WHERE order_id = 1001;

UPDATE products
SET price = price * 1.1
WHERE category = 'Electronics';

UPDATE students
SET status = 'Graduated';

UPDATE customers
SET total_purchases = (
    SELECT SUM(amount)
    FROM orders
    WHERE orders.customer_id = customers.customer_id
)
WHERE customer_type = 'Premium';

<?php
$dbhost = 'localhost';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = '123456';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
 
$sql = 'UPDATE runoob_tbl
        SET runoob_title="学习 Python"
        WHERE runoob_id=3';
 
mysqli_select_db( $conn, 'RUNOOB' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
    die('无法更新数据: ' . mysqli_error($conn));
}
echo '数据更新成功！';
mysqli_close($conn);
?>