How You Add a Warning Message Using Autocomplete Rules
The Add warning message option enables you to insert a rule line that shows a warning message to the user. This option can only be used in the Field Modification rule type.
You can't show a warning in Business Object Defaulting, Business Object Validation and Field Validation rule types. This option is mostly available inside a conditional statement. Unlike the Add error message option, you can continue to add additional rule lines to execute. This works like an information message and there's no option to revert user input or modifications.
You can only view the warning message and dismiss it by clicking OK. The warning statement, by default, is shown as an equation, similar to an error statement. You can change the right hand side of this equation in the same way as in the Add error message option.
A point to note is that you can't use curly brackets or double quotes in a warning message. Other types of brackets must be used in pairs, that's any open brackets including { or ( must be closed and vice-versa.
You can translate warning messages added using Autocomplete Rules in all Oracle supported languages. But, you need to use only one language when implementing and maintaining messages, otherwise the translation will be overridden. If the rule is edited in another language and saved while the message is already translated, then the message is overridden and translation will be lost.