when does 'ora-1007 variable not in select list ' occur?

hi gurus,

in what instances 'ora-1007 variable not in select list ' occurs?

i'm having difficult in tracing the cause of it in my process. because when i rerun the process w/ the same data set. it didn't occur again.... it's very intermitent.

thanks
Best regards,
Grace Lim
Suy Sing Comm'l Corp.
(063)-02-247-41-34

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