Issues encountered by Oracle in creating stored procedures

Create or replace PROCEDURE CLEAR as
Tname varchar (200);
BEGIN
tname:= ' immediate trace name Flush_cache ';------->> in this sentence, the function of single quotation marks is equivalent to an escape character, and one of the single quotes is escaped to the single quotation mark to be used. does not represent the identity of the string in Oracle, which means that the statement "represents a single quotation mark."
Execute immediate ' alter session set events= ' | | tname; --->> | | A connector that represents a string
Execute Immediate ' Alter system flush Shared_pool '; ---->>execute Immediate executes the statement enclosed in single quotation marks.
--Dbms_output.put_line (' hhhhhhhhkkkkkkk ');
Commit
END CLEAR;

Issues encountered by Oracle in creating stored procedures