CachedStore is a very good new feature to alleviate the pressure on the background database.
The Function Cache is a function that the CachedStore feature has not been completed.
This patch completes the Function Cache.
The functional points involved are as follows:
1) Function Cache prewarm
2) Function Cache Update
3) CreateFunction、AlterFunction、DropFunction、GetFunction .
4) NotificationEvents (CREATE_FUNCTION_EVENT、DROP_FUNCTION_EVENT)