transaction.md

# Transaction

下列选项中，哪个可以正确的保证 channel 表和 posts 表的同步修改？

## 答案

```sql
begin;
    insert into posts(title, content) select ?, ?;
    update channel set posts = posts +1 where channel_id = ?;
commit;
```

## 选项

### 没有 commit

```sql
begin;
    insert into posts(title, content) select ?, ?;
    update channel set posts = posts +1 where channel_id = ?;
end;
```

### 没有创建事务

```sql
insert into posts(title, content) select ?, ?;
update channel set posts = posts +1 where channel_id = ?;
commit;
```

### 多次提交

```sql
begin;
    insert into posts(title, content) select ?, ?;
commit;
    update channel set posts = posts +1 where channel_id = ?;
commit;
```