Mysql stored procedure questions and app questions

When I was working on an app recently, I used the stored procedure and suddenly had some ideas. please ask me the traditional app structure. 1 app requests the web server. 2 web server. call the script language to operate on the database. 3. the database returns the result to the web server. 4 if the web server returns the result to the app, can the app directly request the db? Assuming that the db can be requested to be executed in the form of a process in the public network app segment, then the 1app requests the Database 2 the database returns data to the app, which is equivalent to saving the web server link. assuming that the db can withstand concurrency if IOcachecpu is large enough, do not consider whether such architecture is... mysqlapp stored procedure

When I was using the stored procedure for an app recently, I suddenly had some ideas.
Traditional app structure
1 app request web server
2. the web server calls the script language to operate the database.
3. the database returns the result to the web server.
4. the web server returns the result to the app

Can the app directly request the database?
Assume that the database can request
The execution in the form of a process in db becomes
1 app request database
2. the database returns data to the app.
This is equivalent to saving the web server.

Assuming that the concurrency I/O cache cpu capacity that the db can afford is large enough without considering the later maintenance and update, is this architecture feasible? What are the disadvantages?