http://coskan.wordpress.com/2007/04/23/oracle-idiosyncrasies-2/

Though it did remind me of the colleague who couldn’t work out why he got a “missing expression” error with something like this:

EXECUTE IMMEDIATE
‘SELECT –+ FULL(e) ‘ ||
‘ COUNT(*) ‘ ||
‘FROM emp e ‘ ||
‘WHERE e.empno = 42′ INTO v;

But, I can think of at least a couple of situations that have nothing to do with LOVs in Oracle Forms and where double hyphen style comments inside SQL can cause problems.

While debugging ColdFusion web applications, the SQL used in these applications is logged, usually as a long string with no line breaks. Having a double hyphen comment in the middle of it will cause a problem when trying to execute it as is. I usually need to edit the SQL first, which is a hassle. I think this is indirectly related to Gary’s comment above.

The second situation is, well, rather simple. For example:

SQL> select * from dual;

D
-
X

SQL> select * -- comment here from dual;
select * -- comment here from dual
                                 *
ERROR at line 1:
ORA-00923: FROM keyword not found where expected

SQL> select * /* comment here */ from dual;

D
-
X

Powel also shared an interesting thing about comments in SQL*Plus.

By the way, the stupid Markdown syntax ate the asterisks *. Sorry. I used the backslash \ to escape it.