Counting unique values occouring in a month

[PeterCol]

I have a table recording contacts and date contacted over a period of years. I wish to count the number of unique contacts per month so that regardless of whether they have been in contact once or ten times in that month they are counted only once per month. Ideally I would like to do this with a single query if it is possible.

Thanks

 

[jobb]

how about 2 queries?

first query:

calculated fields

GROUP BY
Year: DatePart("yyyy",[Date])
GROUP BY
Month: DatePart("m",[Date])
GROUP BY
[CONTACT]

second query
(based on first query)
GROUP BY
[YEAR]
GROUP BY
[MONTH]
COUNT
[CONTACT]

 

[ddeldeb]

You could also try a SELECT Distinct(contacts), from......
But just the slightest difference in a record will make it distinct so you need to be a little carefull on what fields you use.

 

[PeterCol]

Yes the 2 queries work thanks. Just not as tidy as one and I need to repeat the queries for numerous other fields.

thanks again.