Checking for Overlaping Date Range

Hi All,

In my program, the users need to enter two dates which represent the vacation range, which, supposedly, not to overlap with other vacation ranges. If there is vacations in the databases, I can check the newly input data against them. However, if there is not, i have to check the ranges record by record before i commit them. Then the problem comes:-

1. I can't use Post-Record, When-Validate, Post-Text-Item types of triggers cos i need to loop thru the records to check (it involves GO_RECORD(#);
2. I can't check in Key-Commit trigger before the command COMMIT cos i'll use RAISE FORM_TRIGGER_FAILURE to stop the program when there is overlapping date range. The reason is RAISing such failure activates a dialog box which ask me whether i want to save the changes. It gives me "Yes, No, and Cancel" options. So, the users can save those overlapping dates...
3. I can't use PL/SQL table which acts as an array in Form. Because my version PL/SQL doesn't support such useful function.

Thenard

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