Using variable as a table name

Question

hi i want to use a variable as table in plsql block
like
declare cursor c1
select to_char(to_date(substr(appl_uid,21,2),'MM'),'MON')||'_'|| as v_Tab,ename from my_table;
v_ename = varchar(55);
vv_table =varchar(6);
begin
open c1
fetch c1 into vv_table,v_ename
select ename into v_ename from vv_table;
DBMS_OUTPUT.PUT_LINE (v_ename);
close c1
end;
please help me to correct this block

Answer 1

As mentioned by BlueShadow above the following statement will fail if the table has more then one row.
EXECUTE IMMEDIATE 'select ename from ' || vv_table INTO v_ename;So I would suggest you use ref curosr to execute a SELECT dynamically which is likely to return more then one row.
SQL> create table my_table (appl_uid VARCHAR2(30),ename varchar2(30));
Table created.
SQL> insert into my_table values ('123456789012345678901234567890','SCOTT');
1 row created.
SQL> insert into my_table values ('123456789012345678901123456789','WARD');
1 row created.
SQL> create table nov_ (ename varchar2(30));
Table created.
SQL> insert into nov_ values ('SMITH');
1 row created.
SQL> insert into nov_ values ('JAMES');
1 row created.
SQL> insert into nov_ values ('JONES');
1 row created.
SQL> create table dec_ (ename varchar2(30));
Table created.
SQL> insert into dec_ values ('ALLEN');
1 row created.
SQL> insert into dec_ values ('ADAMS');
1 row created.
SQL> insert into dec_ values ('KING');
1 row created.
SQL> commit;
Commit complete.
SQL> set serveroutput on
SQL> declare
  2        cursor c1 is
  3        select to_char(to_date(substr(appl_uid, 21, 2), 'MM'), 'MON') || '_' as v_tab,ename
  4        from my_table;
  5        type ref_cur is ref cursor;
  6        c2 ref_cur;
  7        v_ename   varchar(55);
  8  begin
  9        for rec in c1 loop
10          open c2 for 'select ename from ' || rec.v_tab;
11          DBMS_OUTPUT.PUT_LINE('********************'||rec.v_tab||'********************');
12          loop
13              fetch c2 into v_ename;
14              exit when c2%notfound;
15              DBMS_OUTPUT.PUT_LINE(v_ename);
16          end loop;
17          close c2;
18        end loop;
19 end;
23 /
********************DEC_********************
ALLEN
ADAMS
KING
********************NOV_********************
SMITH
JAMES
JONES
PL/SQL procedure successfully completed.And at last as suggested by fellow members that it is a bad idea, I would agree and suggest you to relook your design.
Edited by: zahid79 on Jul 22, 2010 10:28 PM