Qualifying columns to improve performance?

[Arn Klammer]

At a course some years ago, we were told that in join statements, we should qualify ALL our column names with the appropriate table name, not just those that may be ambiguous. The reason was that the parser would not need to spend time checking multiple tables to determine the table to which each column belongs.   Is this still a valid rule?   Does this apply to statements in PL/SQL procedures/packages?  Or are they different, because they are checked at compile time?    -a ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept by MIMEsweeper for the presence of computer viruses. www.mimesweeper.com **********************************************************************