导出成 CSV 格式要点
- FIELDS TERMINATED BY ',' 指定列之间用逗号分隔
- ENCLOSED BY '"' 给每个字段套上双引号，避免内容里的逗号捣乱
- OPTIONALLY ENCLOSED BY 只给字符串套引号，数字不加，更干净
- LINES TERMINATED BY '\n' 用换行区分行，Windows 下常写成 '\r\n'
- 导出带计算列也行：SELECT 里写 a, b, a+b 把运算结果一并落盘
导出成 CSV 格式示例
-- 导出标准 CSV，字符串字段用双引号包裹
SELECT id, username, created_at
INTO OUTFILE '/var/lib/mysql-files/user_export.csv'
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY '\n'
FROM user;
-- 带一列运算结果一起导出
SELECT product_id, price, stock, price * stock AS total_value
INTO OUTFILE '/var/lib/mysql-files/stock_value.csv'
FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n'
FROM product;
避坑提醒：CSV 里如果某个字段本身含逗号或换行，不套引号就会错位。优先用 OPTIONALLY ENCLOSED BY '"'，和 Excel 的默认导出保持一致。
