Get mean value of related fields

[Marcel1]

Hi,

I have a table called "sequence" with records of the sort

[color:green]Patient - text

[color:green]Time - number

[color:green]Sample - text

[color:green]SeqLength - number

In Sequences, there are often several entries that share the same [color:green]Patient, [color:green]Sample and [color:green]Time values.

I have a related table "Visits" that has a single record for every unique Patient/Time /Sample combination (ie a many-to-one from Sequences to Visits). In Visits, I would like to have a field [color:red]AveSeqLength that is the mean of all of the [color:green]SeqLength entries from matching records in Sequences. Does anyone have any idea of how to do this?

Many thanks,

Marcel

(I originally posted this as a multi-part problem in the database schema forum, but since then have solved the database part of it)

[Ender]

Try:

AveSeqLength (calculation, number result) = Average(sequence::SeqLength)

[Marcel1]

That worked great! Thanks,

Marcel