Using 'execute immediate'

Question

Hi,
for instance, we have 4 parameters for that, i remember we should use each parameter ONLY ONCE within the statement. am i right? Or we can reuse each parameter again and again?
like
execute immediate 'select ...
where :4=''a''
and :4<>'' '''
Rgds,
HuaMin

Answer 1

Unfortunately I don't think so you can reuse the same parameter.
  1  declare
  2  v_sql varchar2(2000);
  3  v_no number;
  4  v_count number;
  5  begin
  6  v_no := 7369;
  7  v_sql := 'select count(*) from emp where empno = :1 and sal = :1';
  8  execute immediate v_sql into v_count using v_no ;
  9  dbms_output.put_line('Count is : ' || v_count);
10* end;
SQL> /
declare
ERROR at line 1:
ORA-01008: not all variables bound
ORA-06512: at line 8
  1  declare
  2  v_sql varchar2(2000);
  3  v_no number;
  4  v_count number;
  5  v_sal  number;
  6  begin
  7  v_no := 7369;
  8  v_sal := 800;
  9  v_sql := 'select count(*) from emp where empno = :1 and sal = :1';
10  execute immediate v_sql into v_count using v_no, v_sal ;
11  dbms_output.put_line('Count is : ' || v_count);
12* end;
SQL> set serveroutput on
SQL> /
Count is : 1
PL/SQL procedure successfully completed.
After swapping the variable names v_sal, v_no
  1  declare
  2  v_sql varchar2(2000);
  3  v_no number;
  4  v_count number;
  5  v_sal  number;
  6  begin
  7  v_no := 7369;
  8  v_sal := 800;
  9  v_sql := 'select count(*) from emp where empno = :1 and sal = :1';
10  execute immediate v_sql into v_count using v_sal, v_no ;
11  dbms_output.put_line('Count is : ' || v_count);
12* end;
SQL> /
Count is : 0
PL/SQL procedure successfully completed.Hope this helps
Regards
Raj