EXECUTE IMMEDIATE Temp table in oracle does not get created ORA-00942

Question

Based on this answer I was trying to create temp table, however I am getting exception ORA-00942:table or view does not exist I would assume there is something wron

Answer 1

'CREATE OR REPLACE GLOBAL TEMPORARY TABLE TempQandA(column1 number) ON COMMIT PRESERVE ROWS';

The keyword REPLACE is incorrect. You need to simply create the GTT and insert the values into it using EXECUTE IMMEDIATE :

SQL> BEGIN
  2  EXECUTE IMMEDIATE 'CREATE GLOBAL TEMPORARY TABLE Temp_gtt(column1 number) ON COMMIT PRESERVE ROWS';
  3  EXECUTE IMMEDIATE 'insert into temp_gtt(column1) values(1)';
  4  END;
  5  /

PL/SQL procedure successfully completed.

SQL>
SQL> select * from temp_gtt;

   COLUMN1
----------
         1

SQL>

Answer 2

You dynamically create the GTT, so your INSERT too should be dynamic..

Note that, PL/SQL validates every static query before even executing it. Thats why you get ORA-942 Table or view doesn't exist error even at compilation time!

So, to escape this semantic check, we have to make the call dynamic.

    BEGIN
    EXECUTE IMMEDIATE 'CREATE GLOBAL TEMPORARY TABLE TempQandA(column1 number) ON COMMIT PRESERVE ROWS';

.....

    EXECUTE IMMEDIATE ' insert into TempQandA(column1) VALUES (1)';
    END;

And Finally, you should not be creating the GTT on run time.. To avoid such issues. The GTT is anyway going to local to every session.

EDIT: As Lalit says, GTT's DDL doesn't accept CREATE OR REPLACE