MySQL 語法以英文單詞為主，可讀性高。掌握關鍵字大寫習慣、基本查詢結構、逐步學習路徑。

基本查詢結構

SELECT column_list
FROM table_name
WHERE condition
GROUP BY group_columns
HAVING group_condition
ORDER BY sort_columns
LIMIT offset, count;

常用關鍵字 (建議大寫)

SELECT, FROM, WHERE, INSERT, UPDATE, DELETE,
JOIN, INNER, LEFT, RIGHT, ON,
GROUP BY, HAVING, ORDER BY, LIMIT,
CREATE, ALTER, DROP, INDEX, VIEW,
PRIMARY KEY, FOREIGN KEY, UNIQUE, NOT NULL,
AND, OR, NOT, IN, BETWEEN, LIKE, IS NULL

範例：從表撈資料

$result = mysql_query("SELECT * FROM example");  // 旧版 mysql_* 已棄用
// 現代寫法
$stmt = $pdo->query("SELECT * FROM example");
while ($row = $stmt->fetch()) { ... }

學習策略建議

1. 先跑通 SELECT、INSERT、UPDATE、DELETE 基本 CRUD。
2. 理解 JOIN 邏輯 (INNER/LEFT/RIGHT) 與關聯查詢。
3. 學會 GROUP BY + 彙總函式產出報表。
4. 掌握索引原理與 EXPLAIN 執行計畫分析。
5. 實作交易 (Transaction)、預處理語句、參數綁定防注入。

大小寫習慣

關鍵字大寫、表名/欄名小寫、字串值保持原案，提升可讀性：

SELECT u.id, u.name, p.title
FROM users AS u
LEFT JOIN posts AS p ON u.id = p.user_id
WHERE u.status = 'active'
ORDER BY u.created_at DESC
LIMIT 20;