Ensure database and cache consistency

programme 1： Sync delete

The core processes ：

Update the database data first

Then delete the cached data

The problem is ：

1） Failed to delete cache. Dirty data exists

2） It is difficult to collapse all update database entries
Modify directly in the database , Cache does not change

---

programme 2： Delay double delete

The core processes ：

Delete cached data

Update database data

Wait for a short time

Delete the cached data again

The problem is ：

1） The delay time is difficult to confirm

Whether it's a delay of a second or a few seconds , It's actually hard to confirm , You can't delay for a few minutes , Because if you delay for a few minutes , Then there may be dirty data in these minutes , So it's hard to determine the time .

2） The consistency of data cannot be absolutely guaranteed

---

programme 3： Asynchronous monitoring binlog Delete + retry

The core processes ：

Update the database

monitor binlog Delete cache

Cache deletion fails through MQ Try again and again , Until the deletion is successful
The overall flow chart is as follows ：

Refer to how to ensure the consistency of cache and database （ Super detailed case ） Database cache consistency solution