The way that the LEI and DECS 1:n functionality works is based on a common key that is used to identify a group of records. An example of this would be a relational table of invoice items. There would be 1 to n items on the invoice and each item record would have the invoice nubmer as its common grouping key. To solve the problem you need determine the appropriate common key that all the matching rows in the view share. Once you have determined the common key, try a query from the Oracle PL/SQL window (or a gui tool, if you have one). The query would be something like "select * from my_view where key_column = 'keyvalue';" This should return you 1 to n rows for the 'keyvalue' specified. If that works okay then you should be able to mimic the functionality in DECS. Note: you might not need to use the/a View for this type of operation; in my experience Views can effect performance if more than two tables are being joined. If you require the View be sure to have your dba create an index, which will improve your performance.
This was first published in September 2002