How to make a bind variable out of a comparison like statement

Question

I have a statement similar to the following -
select x from atable where acolumn like '1%';
How do I turn that into a variable in an anonymous block like -
declare
l_var varchar2(1) := '1';
begin
select x from atable where acolumn like 'l_var%'
end;
I need to prevent the database from using a literal in the plan so I need to convert like '%1' into a variable.
Any suggestions?

Answer 1

Not quite sure what you mean by 'binding' or 'substitution'.
If you mean bind variables, the yes oracle does automatically use bind variables:
SQL> CREATE TABLE atable
  2  (
  3          x VARCHAR2(10)
  4  )
  5  /
Table created.
SQL>
SQL> INSERT INTO atable VALUES ('1234');
1 row created.
SQL> COMMIT;
Commit complete.
SQL>
SQL> set serveroutput on size unlimited
SQL>
SQL> declare
  2    l_var atable.x%TYPE := '1';
  3    l_str atable.x%TYPE;
  4  begin
  5    select x
  6      into l_str
  7      from atable
  8     where x like l_var || '%';
  9
10    dbms_output.put_line ('l_str = "' || l_str || '"');
11  end;
12  /
l_str = "1234"
PL/SQL procedure successfully completed.
SQL>
SQL> SELECT SQL_TEXT FROM v$sql WHERE sql_text LIKE 'SELECT %ATABLE%' AND sql_text NOT LIKE '%V$SQL%';
SQL_TEXT
SELECT X FROM ATABLE WHERE X LIKE :B1 || '%'
SQL>Where that is the sql statement that the sql engine actually ran on behalf of the pl/sql routine.
GP>