Reason for ddl command in code..!

Question

Hi all,
many times 1 question is asked to me in interviews,
why we can not use create table command in plsql code without "execute immediate stmnt" in below code.
create procedure p1
as
begin
execute immediate 'create table pctab as select * from emp' ;
execute immediate 'trunccate table pctab' ;
update emp
set sal=100 ;
commit ;
end p1;
kindly ans....why we can not use create table command in plsql code without "execute immediate stmnt" in below code.
regards,
PC

Answer 1

Hi,
In PL/SQL, you can only use PL/SQL statements. Something may be a perfectly good statement in SQL (or Java, or German, or any other language) but it won't work in PL/SQL if it's not a PL/SQL command.
"CREATE TABLE" is not a PL/SQL command, so you can't use it in PL/SQL.
There are some commands that are both PL/SQL statements and SQL statements (just like there are some English words that also mean the same thing in German). UPDATE and ROLLBACK are a couple of examples. Those are things people often want to do in PL/SQL.
If people frequently wanted to create tables in PL/SQL, then Oracle might make a PL/SQL "CREATE TABLE" command, just like Oracle made UPDATE a PL/SQL command. But the fact is, people don't do that very often (whether that is "pure evil" or not), and there is already a way to create tables (or to run any other SQL command, namely EXECUTE IMMEDIATE) for those rare occasions when you do need to do it in PL/SQL.