I would like to ask what is this that many statements in SQL databases like to use. For example: view_name and many other underscores are used in database statements.

This,

As far as I am concerned, my personal habit is actually a marking function

I like to use _sp in the definition process

I like to use _uf to define functions

I like to use v_ to define views (the same as your view_)

I like to use tr_,,,, to define triggers