Hi Nadya,
Good to see you too :-) (Funny, I thought you would be the first person to reply to my first ever message on UT)
Possibly triggers can do the job. I will look into that. But I thought about another approach, right after I posted my initial message. I am thinking about creating a view with a calculated field. I have never had a view with a calculated field on sum in another table so I don't know if it will work. I know by the end of the day I will know if it works.
Thank you for your helpful suggestion.
Dima
"The creative process is nothing but a series of crises." Isaac Bashevis Singer
"My experience is that as soon as people are old enough to know better, they don't know anything at all." Oscar Wilde
"If a nation values anything more than freedom, it will lose its freedom; and the irony of it is that if it is comfort or money that it values more, it will lose that too." W.Somerset Maugham