Explain Plan Failure due to bind variable

In some cases, explain plan like below fails due to undeclared bind variable in session.

explain plan set statement_id = 'some_id' for select * from some_table where some_column = :SOME_BIND_VARIABLE;

However, in some cases it works even though the bind variable is not declared in current session. I have no clue what makes this difference. Could somebody enlighten me why? Thank you in advance. Received on Thu Mar 07 2002 - 10:10:18 CST