Redis vs MySQL 总结

MySQL	Redis
INSERT	SET / HSET
SELECT	GET / HGET / HGETALL
UPDATE	SET / HSET
DELETE	DEL / HDEL
SELECT * WHERE id IN (...)	MGET
SHOW TABLES	KEYS * / SCAN
BEGIN ... COMMIT	MULTI ... EXEC
USE DATABASE	SELECT n

1. 插入数据（INSERT）

MySQL: INSERT INTO users (id, name, age) VALUES (1, 'Alice', 25);

Redis:
SET user:1:name "Alice"
SET user:1:age 25

2. 查询数据（SELECT）

MySQL: SELECT name FROM users WHERE id = 1;

Redis:
GET user:1:name

3. 更新数据（UPDATE）

MySQL: UPDATE users SET age = 26 WHERE id = 1;

Redis:
SET user:1:age 26

4. 删除数据（DELETE）

MySQL: DELETE FROM users WHERE id = 1;

Redis:
DEL user:1:name
DEL user:1:age

5. 设定过期时间

MySQL: DELETE FROM sessions WHERE expire_time < NOW();

Redis:
SET session:123 "user1" EX 3600
EXPIRE session:123 3600

6. 计数操作

MySQL: UPDATE users SET login_count = login_count + 1 WHERE id = 1;

Redis:
INCR user:1:login_count

7. 查询多个数据

MySQL: SELECT * FROM users WHERE id IN (1, 2, 3);

Redis:
MGET user:1:name user:2:name user:3:name

8. 列出所有键

MySQL: SHOW TABLES;

Redis:
KEYS *  # 不推荐生产使用
SCAN 0 MATCH user:*

9. 事务

MySQL:
BEGIN;
UPDATE users SET balance = balance - 100 WHERE id = 1;
UPDATE users SET balance = balance + 100 WHERE id = 2;
COMMIT;

Redis:
MULTI
DECRBY user:1:balance 100
INCRBY user:2:balance 100
EXEC

10. 数据库切换

MySQL: USE my_database;

Redis:
SELECT 0  # 选择数据库 0
SELECT 1  # 选择数据库 1